IMAGE  EVALUATION 
TEST  TARGET  (MT-3) 


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11.25 


£  Itf   |2C 


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Hiotographic 

Sdences 

Corporation 


23  WIST  MAIN  STRtr 

WEBSTill,N.Y.  MStO 

(716)072-4903 


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CIHM/ICMH 


Series. 


CIHM/ICMH 
Collection  de 
microfiches. 


Canadian  Institute  for  Historical  Microreproductions  /  Institut  Canadian  de  microreproductions  historiquas 


,.■•<. 


m 


Tachnical  and  Bibliographic  NotM/NotM  t«ehniqu«s  at  bibllographiquM 


Th 
to 


Tho  Inttltuto  Hm  attomptod  to  obtain  tho  bast 
original  copy  avaNaMa  for  filming.  Faaturaa  of  thia 
copy  which  may  ba  MbHograpMcaNy  unlqua. 
which  may  altar  any  of  tha  imagaa  in  tha 
reproduction,  or  which  may  significantly  changa 
tha  usual  mathod  of  filming,  ara  chackad  balow. 


D 
D 
D 

n 

D 
D 
D 
D 

D 


Colourad  covers/ 
Couvartura  da  coulaur 

Covars  damagad/ 
Couvartura  andommagAa 

Covars  tastorad  and/or  iaminatad/ 
Couvartura  rastaurAa  at/ou  paiiiculAa 

Covar  titia  missing/ 

La  titra  da  couvartura  manqua 

Colourad  maps/ 

Cartes  gAographiques  en  couleur 

Coloured  inic  (i.e.  other  than  blue  or  blacic)/ 
Encre  de  couleur  (i.e.  autre  que  bieue  ou  noire) 

Coloured  plates  and/or  illustrations/ 
Planchee  et/ou  illustrations  en  couleur 

Bound  with  other  material/ 
ReliA  avac  d'autres  documents 

Tight  binding  mey  cause  shadows  or  distortion 
along  interior  margin/ 

La  re  liure  serrie  peut  causer  de  I'ombre  ou  de  le 
distortion  le  long  de  ie  marge  intArieure 

Bianic  leaves  added  during  restoration  may 
appear  within  the  text.  Whenever  possible,  these 
have  been  omitted  from  filming/ 
11  se  peut  que  certaines  pages  blanches  ajouttes 
lors  d'une  restauration  apparaissent  dans  ie  texte. 
meis.  lorsque  cela  Atait  possible,  ces  pages  n'ont 
pas  4tA  fiimAes. 


L'institut  a  microfilm*  le  meilleur  exempleire 
qu1l  lui  a  AtA  possible  de  so  procurer.  Lee  dAteils 
da  cot  exemplaira  qui  sent  peut-ttre  uniquee  du 
point  de  vue  bibHographiqua,  qui  peuvent  modifier 
une  image  reproduite,  ou  qui  peuvent  exiger  une 
modificetion  dens  la  mAthode  normale  de  filmege 
sont  indiquto  ci-dessous. 


r~y|   Coloured  pages/ 


D 
D 


Pages  de  couleur 

Pages  damsged/ 
Pages  endommegtes 

Pages  restored  end/oi 

Peges  restaurAes  et/ou  peiliculAes 

Pages  discoloured,  stained  or  foxei 
PagM  dAcolortes,  tachettes  ou  piquies 

Pages  detached/ 
Pages  dAtachtes 

Showthrough/ 
Transparence 


r~n  Pages  damsged/ 

I — I  Pages  restored  end/or  laminated/ 

r~7]  Pages  discoloured,  stained  or  foxed/ 

I     I  Pages  detached/ 

[^  Showthrough/ 


Th 
po 
of 
fill 


Or 
be 
th( 
sio 
oti 
fin 
sio 
or 


I     I   Quality  of  print  varies/ 


QuaiitA  inAgaia  de  I'impression 

includes  supplementary  materiel/ 
Comprend  du  materiel  suppiAmentaire 


Th 
sh 
TH 
w» 

Ml 
dif 
en 
bei 
rig 
rec 
mi 


Only  edition  available/ 
Seule  Edition  disponible 

Pages  wholly  or  partially  obscured  by  errata 
slips,  tissues,  etc.,  have  been  refilmed  to 
ensure  the  best  possible  image/ 
Les  pages  totaiement  ou  partiellement 
obscurcies  par  un  feuiliet  d'errata,  une  pelure, 
etc.,  ont  4t6  fiim^es  A  nouveau  de  fapon  d 
obtenir  la  meilieure  image  possible. 


0    Additional  comments:/ 
Commentaires  suppiimentaires; 


Irragular  pagination  :  [1]  32,  [1]  •  7, 33-72  p. 


This  item  is  filmed  at  the  reduction  ratio  checlced  below/ 

Ce  document  est  fiimA  ou  taux  de  rMuction  indiqui  ci-dessous. 


10X 

14X 

18X 

22X 

26X 

30X 

J 

12X 


16X 


20X 


24X 


28X 


32X 


Th*  copy  filnMd  har*  hat  bMn  r«produe«d  thanks 
to  tha  ganarosity  of: 


Library  of  tha  Public 
Arehivas  of  Canada 


L'axamplaira  fllm4  fut  taproduH  grica  A  la 
gAn«roalt«  da: 

U  MbliothAqua  daa  Arohh^ 
pubHquas  du  Canada 


Tha  imagaa  appaaring  hara  ara  tha  baat  quality 
poaaibia  eonaidaring  tha  condition  and  lagiblNty 
of  tha  original  copy  and  in  kaaping  with  tha 
filming  contract  apaciflcatlons. 


Original  copias  In  printad  papar  covara  ara  fllmad 
baglnning  with  tha  front  covar  and  anding  on 
tha  last  paga  with  a  printad  or  liiustratad  impras- 
sion,  or  tha  back  covar  whan  approprlata.  All 
othar  original  copiaa  ara  filmad  baglnning  on  tha 
first  paga  with  a  printad  or  liiustratad  Impraa- 
sion,  and  anding  on  tha  last  paga  with  a  printad 
or  liiustratad  imprassion. 


Tha  last  racorded  frama  on  aach  microficha 
shall  contain  tha  symbol  ^^-  (moaning  "CON- 
TINUED"), or  tha  symbol  V  (moaning  "END"), 
whichavar  applias. 


Laa  Imagaa  suhrantaa  ont  *t4  raproduitaa  avac  la 
plus  grand  soin.  compta  tanu  da  la  condition  at 
da  la  nattat*  da  raxamplaira  fllmA.  at  an 
conformity  avac  las  conditions  du  contrat  da 
fllmaga. 

Laa  axamplalras  orlglnaux  dont  la  couvartura  an 
papiar  aat  ImprlmAa  sont  film4s  an  commanfant 
par  la  pramlar  plat  at  an  tarminant  salt  par  la 
darnlAra  paga  qui  comporta  una  ampralnta 
d'Impraasion  ou  d'lllustration.  soit  par  la  sacond 
plat,  salon  la  cas.  Tous  las  autras  axamplalras 
orlglnaux  sont  fllmto  an  commandant  par  la 
pramiAra  paga  qui  comporta  una  ampralnta 
d'imprasslon  ou  d'illustratlon  at  an  tarminant  par 
la  darnlAra  paga  qui  comporta  una  talla 
ampralnta. 

Un  das  symbolas  suivants  apparattra  sur  la 
darnlAra  Imaga  da  chaqua  microficha.  salon  la 
cas:  la  symbols  — ^  signifia  "A  8UIVRE",  la 
symbols  ▼  signifia  "FIN". 


Maps,  piatas.  charts,  ate.  may  ba  filmad  at 
diffarant  raduction  ratios.  Thoss  too  iarga  to  ba 
antiraly  included  in  ona  axposura  ara  filmad 
baglnning  in  tha  uppar  iaft  hand  corner,  laft  to 
right  and  top  to  bottom,  as  many  framas  as 
rsquirad.  Ths  following  diagrams  illustrata  tha 
method: 


Las  cartes,  planches,  tableaux,  etc..  peuvent  Atre 
fiimAs  i  des  taux  da  rMuction  diff Arents. 
Lorsqus  is  document  est  trop  grand  pour  Atre 
reproduit  en  un  seul  clichA,  11  est  filmi  A  partir 
da  I'angle  supArleur  gauche,  do  gauche  A  droite, 
et  de  haut  en  has,  en  prenant  la  nombre 
d'images  nAcesssire.  Les  diagrammes  suivants 
illustrent  la  mAthode. 


1 

2 

3 

'    i 

a 

,a.." 

4 

5 

6 

3=^=?= 


THOMPSON 

mPmvBD 

iHDICflTOR 


MANUFAOTURBO  ONLY  BY 


Amerieao  Steam  Gauge  Co., 

34,  36  1^  38  CHAf(DON  STl^HBT, 

BOSTOH.  PSS. 


flea  YoPk  Broneh: 
61  JOHN  STt^EET,  NEW  VOt^I^. 


Westeni  Braneb: 


16   HOt^TH   CA|4AIi   STt^EET,    CHICAGO,  Ilili. 


WauCM,  VOMM  a  OC,  MWTIM,  U»  Oowwiw  tr. 


/ 


'f 


TI 


•y^SmiWKM  MTABUISMID  IN  1861. 


''^^WS/^* 


IWOOW^OWATtD  IN  ieS4y    lf(» 


t 


(ORXs-zxTJLX.  S7x.^a^  a./i.T7ai-aB  cos^ruk.sT'z-. } 


A]\SEt^ICAH 


■•<;■;;, 


Steiuh  Gauge  Goikpany, 


BOLE  MAMUFACTURRIM  OF  THE 


BOURDON  STEAM  GAUGE. 

WITH    LANE'S    IMPROVEMENT. 

THOMPSON'S  iP  RICHARDS-  STEAM-ENGINE  INDICATORS,  AMSLER'S 

POLAR  PLANIMETER,  THE  PANTOGRAPH,  HUSSEY'S  SPEED 

INDICATOR,  AMERICAN  POP  SAFETY  YALYES. 

ALSO 

Water  Gauges,  Gauge  CocKs,  WI\istles,  Revolution  Counters,  Sett^ 

Ttioir\as  ar\d   Ho-Ward  ClocKs,  Pyron^cU'Cs,  Hydrorqeters 

Salirionieters,  Spring  Balaqces,  Mercurial  Ciption 

Gauges,  Lov)  Water  aqd  Alarrq  Gauges,  ar\d 

all  Kir\ds  of  Steairist\ip  Iqstrun\eqts. 


34,  36  &  38  CHAt^DOH  STt^EET, 


BOSTON,     MASS. 


New  York  Branch, 


Western  Branohi 


% 


.    51  JOHN  STREET,  NEW  YORK.         IS  N.  CANAL  ST  ,  CHICAQO.  ILL   ., 


jSi 


Pmerioai)  3t^am  Qau^^  ^o.,  BostOQ. 


rrrrrrr-r 


OFFICE  AND  MANUFACTORY  OF 

Amemai)  Steam  Gauge  Go. 

NOS.  34,  36  d  38  CHARDON  STREET, 


BOSTON,  MASS. 


New  York  Branch,  51  JOHN  ST.,  NEW  YORK. 


Western  Branchy  16  No.  CANAL  ST.,  CHICAGO,  ILL. 


•^- 


r 


/tmerioaQ  St^am  Oau^e  ^o.,  Bubtop. 


Co. 


THE    THOMPSON    IMPROVED    INDICATOR. 

THE  ONLY  PERFECT  INDICATOR  MADE. 

PATENTED  AITOIHT  :il.  IMia.  JULY  19,  IMl.  A.M>  JirNK  911,  IHIM. 


Fig.  I. -Outside.  Fig.  2.-lntide. 

The  Thompson  Improved  Indicator  was  patented  by  J.  W. 
Thompson,  Aug.  31,  1875  and  July  I3,  1881  ;  and  by  careful  con- 
sideration of  the  demands  of  the  engineering  public,  we  have  from 
time  to  time  improved  it,  and  it  is  now  conceded  by  all  prominent 
engineers  to  be  the  standard  steam-engine  indicator  for  the  U.S.  and 
all  foreign  countries. 

The  radical  improvements,  as  made  in  the  old-style  Thompson 
Indicator,  consists  of  lightening  the  moving  parts,  substituting  steel 
screws  in  ph.ce  of  taper  pins,  using  a  very  light  steel  link  instead 
of  a  large  brass  one,  reducing  the  weight  of  the  pencil  lever,  also 
weight  of  squares  on  trunk  of  piston,  and  lock-nut  on  end  of  spin- 
dle, and  increasing  the  bearing  on  connection  of  parellel  motion. 
By  shortening  the  length,  and  reducing  the  actual  weight  of  the 
paper  cylinder  just  one  half,  and  by  shortening  the  bearing  on 
spindle,  also  lowering  the  spring  casing  to  a  nearer  plane  to  that 
in  which  the  cord  runs,  we  have  reduced  the  momentum  of  the 
paper  cylinder  to  a  very  small  amount.  All  of  these  improvements 
have  lessened  the  amount  of  friction,  which  was  heretofore  very 
small,  but  is  now  reduced  to  a  minimum ;  and,  furthermore,  they 


fim^noat)  8tea/n  Qbuq^  ^o..  BostOQ. 


tend  to  iinprovi',  on  the  whule,  nn  instrument  wIiumc  principle  has 
ulways  heen  of  undoubted  correctneKH. 

In  callin);  attention  to  the  fentures  of  this  instrument,  we  prefer 
to  do  8o  Hubject  to  all  amenities  of  husineHs  courtesy,  leaving;  our 
pnxhictH  to  speak  for  themselves,  an<l  others  to  do  the  same  :  hut,  in 
justice  to  ourselves  and  our  instrument,  we  shall  not  allow  to  paHs 
certain  representations  published  hy  the  makers  of  rivjl  instruments. 

In  the  pamphlet  issued  in  behalf  of  the  Tabor  Indicator  certain 
statements  are  made  as  showing  the  relative  performances  and 
relative  weights  of  moving  parts  of  both  instruments.  To  these 
statements  we  will  simply  state,  the  nuittcr  of  relntivi-  performances 
was  not  done  as  a  public  test,  and  cunnot  be  taken  as  a  basis  of 
comparison.  The  table  of  comparative  weights  was  deducted  by 
comparison  with  the  old-style  Thompson  Indicator,  and  should  not 
be  considered  any  comparison  with  the  Thompson  Improved 
Indicator  as  now  made.  ' 

In  the  circular  issued  by  the  makers  of  the  Crosby  Indicator, 
certain  statements  are  made,  and  diagrams  shown,  tending  to 
depreciate  the  efficiency  of  the  paper-cylinder  spring  of  the  Thomp- 
son Indicator. 

The  machine  used  to  produce  the  diagrams  referred  to  is  one  of 
very  questionable  correctness,  and,  wherever  used  in  public,  has  left 
an  uncertainty,  amounting,  in  fact,  to  a  doubt. 

The  conditions  of  a  test  conducted  in  private  can  never  be  con- 
sidered fair  representations  of  the  competing  instruments;  and,  to 
determine  to  the  satisfaction  of  all  parties  interested,  we  herewith 
challenge  the  makers  of  all  other  indicators  to  an  open  and 
public  test^  to  determine  the  efficiency  of  the  different  instru- 
ments. 

In  the  Crosby  Indicator,  the  paper  drum  spring  is  a  spiral 
spring ;  the  advantages  claimed  for  same  over  the  coil  spring, 
producing,  briefly  stated,  a  "uniform  stress  on  the  cord"  through- 
out the  stroke. 

In  order  to  have  this,  the  force  of  the  spring  should  be  least 
when  the  inertia  of  the  drum  has  to  be  overcome  by  the  cord  in 
opposition  to  the  force  of  the  spring,  and  greatest  when  the  inertia 
is  to  be  overcome  by  the  spring. 

But,  admitting  that  it  is  possible  to  secure  nearly  uniform  stress 
on  the  cord  in  a  given  case,  it  will  be  evident,  that,  to  secure  that 


*? 


w 


l^'^*  pmerkai)  8tcam   (Jaa^e  ^o..  Bostop. 


iciplv  han 

we  prefer 
iiviii);  our 
: :  but,  in 
w  to  pasH 
trumcnts. 
jr  certain 
nces  aiul 
To  these 
ormanccs 
a  basis  of 
luctcd  by 
hould  not 
Improved 

Indicator, 
nding  to 
;  Thomp- 

I  is  one  of 
:,  has  left 

r  be  con- 

and,  to 

herewith 

pen   and 

instru- 

a  spiral 
spring, 
through- 

be  least 
e  cord  in 
jc  inertia 

rm  stress 
cure  that 


i^. 


result,  thire  nui«t  be  perfect  cci-oprrution  anionKut  all  of  the  follow- 
in;;  liutors  :  — 

I.  The  speed  of  tlie  engine. 

i.  The  lenjjlh  of  the  diagram. 

'^.  'I'he  terjsion  of  the  spring. 

4.  The  Unytli  of  the  >.priii<^. 

>,.     The  weight  of  the  drum. 
» 

It  is  evident  that  but  two  of  these  factors  can  be  secured  in  the 
construction  of  the  iiistrumeiU  ;  namely,  the  i'ourth  and  fifth  :  and 
these  beiuy;  once  adapted  to  a  y;i\en  speed,  the  instrument  cannot  be 
adapted  to  any  other  speed,  except  to  the  very  limited  extent  allowed 
by  \ariations  of  the  tensit)n  of  the  spring  or  in  the  length  of  the 
diagram. 

'I'he  difVcrence  re(|iiircd  for  ditVerent  speeds  would,  other  things 
e(|ual  be  (litlerent  lenj^ths  of  spring;  the  slower  s^m  jds  recpiiring 
the  longer  springs  in  inxerse  proportion  to  the  number  of  revolutions 
per  minute.  Tims,  an  instnunent  being  properly  adjusted  for  a 
speed  of  ^(K)  revolutions,  would  retpiire  a  spring  twenty-five  times 
longer  for  a  speed  of  6(j.  that  being  the  square  of  the  ratio  of  the 
two  speeds,  5  to  i . 

Also,  if  applied  to  the  latter  speed  as  adapted  to  the  higher 
speed,  the  stress  on  the  cord  would  vary  nearly  as  nnich  as  the  force 
of  the  spring  ;  and  the  resulting  <liagram  would  be  as  much  shorter 
than  the  movement  of  the  reducing-gear  from  which  it  was  derived, 
as  the  cord  woidd  vary  in  stretch. 

In  point  of  fact,  all  springs,  "volute"  .md  "spiral,"  alike 
possess  the  property  required  for  the  theory  for  all  increase  in 
resistance  as  the  cord  is  drawn ;  and  every  one  is  adapted  to  some 
speed,  though  some  speeds  met  with  are  so  slow  as  to  recpiire  a 
spring  of  more  uniform  resistance  than  could  be  introduced  in 
either  form,  particularly  in  the  spiral  form. 

From  the  foregoing,  it  will  be  seen  that  it  is  utterly  impossible 
to  have  uniform  stress  on  the  cord,  except  at  or  near  the  speed  for 
which  the  spring  is  adapted. 

Furthermore,  in  increasing  the  tension  of  the  spiral  spring,  the 
spring  is  twisted  and  distorted,  thereby  binding  and  throwing  it  out 
of  position,  necessarily  causing  rough  and  imeven  motion  of  the 
whole  drum  movement. 


#! 


t 


/tm^rieai;  Steam  (jauf^  ^o.,  Boetoi). 


'W\ 


% 


The  foregoing  facts  are  not  submitted  to  depreciate  the  instru- 
ment named,  but  are  simply  offered  in  self-defence. 


FEATURES    OF    THE    THOMPSON    IMPROVED 

INDICATOR, 

Parallel    Motion, 

The  Parallel  motion  of  the  Thompson  Improved  Indicator  is 
the  most  accurate  of  anything  used  or  ever  seen  in  the  indicator 
line,  and  errors  said  to  tixist  in  drawing  correct  vertical  lines  do  not 
appear  in  the  limited  movement  of  the  pencil  in  taking  diagrams 
from  a  steam-engine. 

The  p^rellel  movement  of  the  pencil  is  secured  by  u  link 
attached  to  and  governing  the  lever  direct.  The  pivots  of  this  link 
are  made  free  from  any  appreciable  lost  motion,  and  will  remain  so 
indefinitely ;  but,  if  any  such  lost  motion  should  exist,  it  will  affect 
the  integrity  of  the  parellel  movement  only  to  an  extent  equal  to  it, 
uoi  three  or  four  times  that  amount.  The  parellel  movement  will 
be  affected  only  by  the  play  in  the  pivots  of  the  link,  and  not  in  any 
degree  or  manner  by  the  play  of  any  other  parts.  When  the 
parellel  movement  is  affected  by  controlling  the  connecting-rod, 
either  by  a  curved  slot  in  it  and  a  guiding  roller,  or  by  attaching 
the  link  to  it,  as  in  other  instruments^  it  (the  parellel  motion) 
becomes  dependent  for  its  accuracy  on  the  fit  of  several  parts,  play 
in  any  one  of  which  will  cause  an  uncertainty  and  possible 
inaccuracy  in  the  parellel  movement  equal  to  three  or  four  times  the 
amount  of  such  play. 

The  force  required  to  guide  the  lever  in  its  parellel  movement 
is  received  on  the  pivots  of  the  link  alone,  where  the  friction  it 
causes  is  practically  inappreciable. 

With  the  slot  and  roller  device,  this  guiding-force  is  received 
on  several  rapidly  moving  surfaces,  multiplied  in  amount  by  lever- 
age. The  same  is  true  to  a  considerable  extent  of  the  plan  of 
attaching  the  link  to  the  connecting-rod. 

The  Paper-Cylinder  Movement. 

It  is  so  constructed  that  the  tension  of  the  coiled  drum  spring 
within  the  paper  cylinder  can  be  increased  or  decreased,  for  different 


^ 


the  instru- 


9rED 


ndicator  is 

!  indicator 

nes  do  not 

diagrams 

>y   u   link 

f  this  link 

remain  so 

will  affect 

jual  to  it, 

mentwill 

lot  in  any 

^hen   the 

ting-rod, 

attaching 

motion) 

Its,  play 

possible 

:imes  the 

ovement 
ction    it 

received 
y  lever- 
plan    of 


1  sprmg 
lirterent 


f\in^r'iQaT)  Stearn  Cjau^^  ^o.,  BoetOQ. 


^ 


speeds  of  engines.  As  little  or  as  much  of  the  spring  can  be  taken 
up  or  let  out  as  desired,  thereby  providing  for  fine  adjustments,  and 
not,  as  in  other  instruments,  where  a  whole  coil  must  be  taken  up, 
or  noiie. 

For  high  speeds,  our  instrument  will  give  accurate  results  for 
all  practical  purposes,  without  any  special  adjustments  further  than 
to  give  sufficient  tension  to  keep  the  cord  taut  at  all  points. 

When  exceptionally  accurate  work  is  desired,  the  length  of  the 
diagram  may  be  carefully  measured,  and  compared  with  the  length 
of  a  line  traced  on  the  paper  when  the  engine  is  moved  slowly.  If 
the  diagram  is  found  to  differ  in  length  from  this  line,  vary  the 
tension  of  the  spring  till  they  agree.  The  paper  cylinder,  or 
*'  drum,"  we  now  make  with  covered  top. 


Lidding  Pulley  for  Paper  Cylinder-. 

This  latest  improvement  in  the  Thompson  Improved  Indicator 
was  patented  June  26,  1883,  and  consists  (see  Fig.  i)  of  a  wheel 
which  leads  the  cord  through  the  hole,  in  contact  with  the  scored 
wheel,  over  which  the  cord  can  be  run  to  any  possible  angle,  to 
connect  with  the  motion,  wherever  it  may  be,  or  of  whatever  kind. 

The  pulley  works  in  a  sleeve  which  rotates  in  the  st  Kid  accord- 
ing to  the  adjustments  required,  and  which  is  held  in  its  position, 
where  adjusted  by  the  thumb  screw,  which  acts  as  a  binding-screw 
working  in  the  groove  on  the  sleeve.  By  this  it  is  held  in  any 
position  that  may  be  chosen,  and  yet  be  free  to  revolve  the  moment 
the  binding-screw  is  loosened,  without  any  possibility  of  interfering 
with  the  motion  by  means  of  scarring  the  sleeve,  or  disturbing  the 
particles  of  metal  on  surface.  It  also  gives  all  the  desired  freedom 
of  motion  and  facility  of  adjustment. 

By  means  of  the  set  screw,  the  stand  which  carries  the  wheel 
can  be  adjusted  to  run  the  cord  to  any  possible  angle  within  a  range 
of  three  hundred  and  sixty  degrees. 

In  the  double  pulley  arrangement,  as  used  in  other  indicators, 
the  range  of  adjustment  is  limited;  and  in  some  cases  the  cord 
cannot  be  made  to  run  in  a  number  of  certain  directions  without 
iia\  ing  it  run  grating,  rough  and  uneven. 

In  this  improved  swivel  pulley,  the  use  of  carrying-pulleys  is 
done  away  with,  and  from  the  fact,  that,  no  matter  what  the  angle 


*1^ 


f\f[\er\Qa[)  S^(^an\  (jau^^  ^o.,  Bostop. 


of  deflection  may  be,  or  what  direction  it  may  be  necessary  to  take 
the  cord,  it  will  work  smoothly ;  for  the  pulley  face  and  the  face  of 
the  groove  on  the  paper  cylinder  are  always  in  the  proper  position, 
one  with  the  other,  to  take  the  cord  to  the  motion,  wherever  that 
may  be  arranged.  '  •    '  -  •  .-■  V 

In  high-speed  short-stroke  electric-light  engines,  great  range  of 
adjustment  is  very  important ;  for  considerable  trouble  is  experienced 
sometimes,  upon  engines  running  three  hundred  and  fifty  and  three 
hundred  and  sixty  revolutions  per  minute,  in  so  arranging  the  cords, 
as  to  use  independent  arcs,  or  making  such  connections  with  refer- 
ence to  right  lines  that  no  distortion  of  diagram  should  be  given. 

We  are  the  sole  owners  of  the  swivel  pulley,  having  purchased 
the  United  States  patent  from  the  patentee ;  and  we  hereby  caution 
all  parties  against  purchasing  any  other  indicator  having  this  device, 
as  we  shall  hold  them  responsible,  as  well  as  the  manufacturer. 

Stop  Motion. 

It  is  provided  with  a  "  stop  motion"  (see  Fig,  3)  which  is  so 
arranged  that  the  horn-handle  screw  can  be  screwed  up  against  the 

post  or  stojD  placed  midway  be- 
tween paper  cylinder  and  steam 
cylinder  so  as  to  regulate  the 
pressure  of  pencil  lead  upon 
the  paper. 

Springs, 

The  best  and  finest  quality  of 
steel  wire  is  used  in  making  our 
springs  ;  and  they  are  all  wound 
on  a  mandrel,  and  tempered  in 
the  most  careful  manner  by  the 
oldest  and  most  experienced 
workmen  in  the  business. 

All  our  springs  are  wound  on 
mandrels  from  four  to  four  and 
one-half  threads  to  the  inch, 
and  thereby  give  more  wire  to 
each  spring,  and  a  consequent 

less  strain,  than  if  wound,  as  in  springs  of  other   indicators,    on 

mandrels  two  to  three  threads  to  the  inch. 


Fig.  3. 


»ry  to  take 
the  face  of 
r  position, 
;rever  that 

t  range  of 
perienced 
and  three 
the  cords, 
■ith  refer- 
given. 
)urchased 
y  caution 
is  device, 
urer. 


lich  is  so 
ainst  the 
Iway  be- 
ul  steam 
late  the 
d   upon 


lality  of 
ing  our 
wound 
ered  in 
by  the 
ienced 


undon 
ur  and 
inch, 
kire  to 
'quent 
on 


jm 


fim^r'Kaj)  Steam  Qau^^  Qo.,  BostoQ. 


Whatever  grinding  is  done  to  lighten  a  spring,  amounts  to  very 
Vj..ie  ;  in  fact,  at  the  most,  it  is  never  ground  to  cause  more  than  one 
to  three  pounds  difterence  in  one  hundred  pounds ;  and,  when  the 
sensitiveness  of  our  springs  is  considered,  very  little  grinding  will 
produce  this  result. 

All  springs  used  in  other  instruments,  whether  double,  single, 
or  having  a  steel  bead  for  bottom  end,  when  connected,  and  under 
steam  pressure,  do  not  possess  the  freedom  of  movement  claimed, 
but  are,  in  fact,  as  rigid  as  those  made  with  double  heads,  like  ours. 

All  springs  we  make  are  scaled,  providing  for  vacuum  ;  and  the 
capacity  of  any  spring  can  be  ascertained  by  the  following  general 
rule:  Multiply  scale  of  spring  by  2^,  and  subtract  15,  and  the 
result  will  be  the  limit  of  pounds  steam  pressure  to  which  spring 
should  be  subjected.  Example:  40-pound  spring  x  2^  =  100— 
15  =  85   pounds  pressure,  capacity  of  a  40-pound  spring. 

To  adapt  the  Thompson  Improved  Indicator  to  all  pressures, 
we  make  springs  to  any  desired  scale.  The  following  are  the  most 
generally  used  :  8,  10,  1 2,  16,  20,  2^,  30,  32,  40,  48,  50,  56,  60, 
64,  80,  100.  For  pressures  from  6^  to  85  pounds,  a  40-pound 
spring  is  best  adapted  ;  for,  as  40  pounds  pressure  on  a  40-pound 
spring  will  raise  pencil  one  inch,  80  pounds  pressure  on  the  same 
spring  will  raise  pencil  about  two  inches,  which  is  the  usual  height 
of  a  diagram. 

VacuutH  Springs. 

All  our  springs  are  scaled  providing  for  vacuum,  but  close  ex- 
periments have  shov/n  us  that  from  the  fact  that  springs  compress 
and  elongate  in  unlike  proportions,  the  regular  pressure  springs 
vary  about  one  pound  in  fifteen,  or  about  6^  per  cent. 

We  make  a  special  vacuum  sjiring,  regular  thread,  scaled  for 
vacuum  onl}',  which  we  furnish  at  the  regular  price  for  pressure 
spring,  $5.00  each. 

All  of  our  springs  are  subjected  to  a  severe  test  before  leaving 
the  factory,  and  they  will  always  be  found  accurate  in  actual  use. 

To  Change  Springs, 

First,  unscrew  the  milled  nut  at  the  top  of  steam  cylinder;  then 
take  out  piston,  with  arm  and  connections;  disconnect  pencil  lever 
and  piston  by  unscrewing  the  small  knurled-headed  screw  which 
connects  them  ;  remove  the  spring  from  the  piston,  substitute  desired 
one,  and  put  together  in  same  manner,  being  careful,  of  course,  to 


:  I 


pm^ri^aQ   St^am  Qau^e  Qo.,  605(017. 


^P 


screw  the  spring  up  against  shoulder,  and  down  full  to  the  piston  head. 
This  arrangement  for  changing  springs  is  simple,  easy,  and  conven- 
ient, and  does  not  require  the  use  of  any  wrench  or  pin  of  any  kind. 
To  change  springs  in  all  other  instruments,  either  a  pin  or  a 
wrench  must  be  inserted  between  the  coils  of  the  spring,  discon- 
necting the  piston.  By  reason  of  the  form  of  the  coils,  not  overy^j^  of 
an  inch  throw  can  be  got  by  the  pin  or  wrench  at  onetime.  When 
the  piston  is  hot,  the  trouble  attending  such  an  operation  can  be 
imagined.  Furthermore,  in  the  Thompson  Improved  Indicator, 
the  ball  and  socket  joint  is  adjusted  to  scale  with  each  spring  a  com- 
plete vacuum,  or  its  equivalent,  14.7  pounds;  and  this  adjustment 
need  never  be  changed  :  but  in  other  instruments,  every  time  a 
spring  is  changed,  this  adjustment  must  necessarily  be  changed ; 
and  the  re-adjustment,  to  show  a  vacuum  with  each  spring,  rests 
with  the  party  using  indicator. 

Right  and  Left  Hand  Indicators, 


Fig.  4.— Right  Hand. 


Fig.  5.-Left  Hand. 


To  facilitate  the  adjustment  of  the  Thompson  Improved  Indi- 
cator to  all  styles  and  makes  of  en<,Mnes,  we  make  the  Indicator 
right  or  left  hand,  as  desired. 

In  a  right-hand  indicator,  the  peaicil  lever  and  connections,  in 


% 


ID 


^ 


piston  head, 
and  conven- 
of  any  kind. 

a  pin  or  a 
ing,  discon- 
otoverj'j^of 
ne.  When 
tion  can  be 

Indicator, 
>ring  a  corn- 
adjustment 
ery  time   a 

changed ; 
pring,  rests 


)vcd  Indi- 
Indicator 

crions,  in 


pmerieai)  Steam  Qau^e  ^o.,  Bostop. 


m 


swinging  away  frotti  the  paper  cylinder,  swing  to  the  right,,  and 
vice  versa  in  a  left-hana  indicator. 

By  manipulating  the  cord-carrying  arrangement,  a  right-hand 
indicator  can  be  used  right  or  lefl  hand  as  desired ;  and  the  same  is 
true  of  the  lefl  hapd  being  used  right  hand. 

Note. — In  a  left-hand  instrument,  the  thumb  screw  for  tight- 
ening or  loosening  the  drum  spring  has  /^/-hand  thread ;  therefore 
when  desirous  of  tightening  or  loosening  the  drum  spring,  start  the 
thumb  screw  by  turning  to  the  right,  or  just  opposite  to  a  right- 
hand  screw. 


Detent  Motion, 

The  Detent  Motion,  as  applied  to  the  Thompson  Indicator, 
consists  of  a  pawl  mounted  on  a  stud,  in  combination  with  a  spring 
and  ratchet,  by  the  use  of  which  the  paper  cylinder  can  be  stopped 
and  a  change  of  cards  made  without  un-hooking  or  disconnecting 
the  Indicator  cord. 

By  moving  the  pawl  so  as  to  catch  in  the  teeth  of  the  ratchet  on 

base  of  paper  cylinder,  (see  Fig. 
6)  the  latter  is  held  stationary 
as  the  engine  completes  its 
stroke.  The  cord,  being  en- 
tirely free,  runs  loosely  with  the 
motion  of  the  engine,  but  the 
paper  cylinder  being  stationary, 
the  cards  can  be  changed  with- 
out the  least  disturbance  of  ad- 
justments. By  throwing  the 
pawl  out  of  the  ratchet  the 
paper  cylinder  is  released,  and 
inmiediately  resumes  its  stroke 
with  the  engine,  but  care  must 
be  taken  not  to  allow  the  paper 
cylinder,  by  force  of  its  spring, 
'^'fl- "•  to  return  to    the    stop    with    a 

thump ;   this  can  easily  be  done  by  simply  holding  the  cord  slightly 
witli  the  thumb  and   hnger  until  the  beginning  of  the  next  stroke. 
This  device  obviates  the  change  of  adjustments,  and  is  particu- 
larly valuable  to  amateurs  and  others  not  familiar  with  the  use  of  the 


II 


i:  1 


ill 


•W? 


fimemaq  8t^am  Oau^e  ^o.,  Bostop. 


Indicator.  It  is  also  valuable  to  users  ot'  the  Indicator  on  very  quick 
running  electric  lijjht  engines,  and  in  all  cases  where  the  circum- 
stances are  such  that  the  disconnection  of  the  connecting  cord  must 
cause  the  operator  considerable  trouble,  and  the  loss  of  valuable  time. 
Indicators  are  not  ecjuipped  with  Detent  Motion  unless  so  order- 
ed, and  when  so  equipped,  a  slight  extra  charge  is  made. 


PRICK    EXTRA    FOR    WETENT    MOTION, 


•3.00 


Adaptability  of  the  Thomptton  Improvetf  IniHcator  for 
Extreme  High  PresHuren, 


C 

a. 


Thompson   Improved 
Indicator. 

>i'  and  '4  inch  area  pistons. 


All  Thompson  Improved  Indicators  are  provided  with  a  piston 
.798  inch  diaineter==  J  iiich  area,  which,  with  the  100-pound  spring, 
provides  for  indicating  pressure  up  to  350  pounds. 


¥ 


/tm^rieai)  Steam  Oau^^  Qo.,  BostOQ. 


^p 


When  pressure  above  that  is  to  be  indicated,  we  furnish  an  ex- 
tra piston  .564  inch  chanieter^J-inch  area,  vvliich,  when  substituted 
for  the  ^-inch  area  piston,  doul)les  the  capacity  of  each  spring,  there- 
by adapting  the  indicator  for  indicating  pressures  up  to  500  pounds. 

From  the  above,  it  will  be  seen,  that  when  an  indicator  is  fur- 
nished with  the  regular  ^-inch  area  piston,  and  nn  extra  ^-inch  area 
piston  in  addition,  the  instrument  can  be  used  to  indicate  all  press- 
ures from  o  to  500  pounds. 


PRICE    OF    EXTRA     1-4  INCU    AREA    PISTON 


•10.00 


Summing  up  the  features  of  the  Thompson  Improved  Indicator, 
it  will  be  seen  that  it  has  advantages  over  all  others  in  the  following 
points  : — 

It  is  handsome  in  design, — mechanically  and  theoretically  as 
near  perfection  as  it  is  possible  to  obtain, —  convenient,  and  simple 
in  arrangement.  All  its  moving  parts  are  very  light ;  and  it  is  made 
of  materials  carefully  selected  and  admirably  fitted,  thereby  insuring 
durability.  It  is  adapted  for  all  pressures  and  speeds  practicable, 
it  is  adapted  for  application  to  all  situations,  and  its  simplicity  and 
accuracy  recommend  it  to  those  least  experienced  in  the  use  of  an 
indicator. 


General   Use  and   Care  of  the    Thompson    Improved 

Indicator, 

Before  using  indicator,  take  it  apart,  clean  and  oil  it.  Try  each 
part  separately.  See  if  it  works  smoothly :  if  so,  put  it  together 
without  the  spring.  Lift  the  pencil  lever,  and  let  it  fall :  if  perfectly 
free,  put  in  the  spring,  and  connect.  Give  it  steam,  but  do  not  at- 
tempt to  take  a  card  until  it  blows  dry  steam  through  the  relief.  If 
the  oil  from  the  engine  gums  the  indicator,  always  take  it  otY  and 
clean  it. 

Never  use  lead  in  connecting :  it  is  not  necessary,  and  is  liable 
to  get  into  the  instrument.  Attach  indicator  direct  to  the  cock. 
The  lighter  the  spring  used,  the  higher  will  be  the  diagram  pro- 
duced, and,  in  consequence,  the  more  accurate  measurements  can 
be  obtained ;  therefore,  in  selecting  a  spring,  select  one  to  give  dia- 
gram about  two  inches  high. 


13 


ill 

' ''  1 
in 


pf[\er\Qai)  Stea/n  Qau^e  ^o.,  Bostoi). 


In  selecting  a  suitable  spring  for  a  given  pressure,  always  bear 
in  mind  the  following  general  rulf,  as  giving  the  maximum  press- 
ure to  which  each  spring  should  be  sul)jecte<l :  Multiply  the  num- 
ber or  scale  of  spring  by  2A,  and  deduct  15  for  the  vacuum  allowance. 
Example:  40-pinmd  spring  x  2A  =  100— i5=:85  pounds  pressure, 
maximum  pressure  of  a  40  spring.  F(;r  pressure  less  than  the  lim- 
it, of  course,  the  spring  may  be  used  ;  but  that  rests  with  the  oper- 
ator's judgment. 

To  CHANGE  THE  SpRiNO. — First,  unscrew  the  milled  nut  at 
the  top  of  steam-cylinder ;  then  take  out  piston,  with  arm  and  con- 
nections; disconnect  pencil  lever  and  piston  by  unscrewing  the 
small-headed  screw  which  connects  them  ;  remove  the  "spring  from 
the  piston,  substitute  desired  one,  and  put  together  in  same  manner. 

The  spring  should  always  be  firmly  screwed  to  the  shoulder ; 
otherwise  the  pencil  will  not  reach  its  proper  position  on  the  scale. 

By  means  of  the  set  screw  which  binds  same,  the  revolving- 
pulley  which  guides  the  cord  can  be  adjusted  to  guide  the  cord  to 
any  desired  direction. 

Diagrams  with  fine  lines  are  always  preferable ;  therefore  use 
hard  leads,  same  as  sent  with  the  indicator,  and  sharpen  same  with 
a  sharp  knife  or  fine  file. 

Use  only  porpoise  or  fine  watch  oil,  such  as  sent  with  instru- 
ment, in  oiling  the  indicator. 

T'/ie  indicator  should  alvjays,,  after  using^  be  taken  apart^ 
and  thoroughly  cleaned  and  oiled. 


14 


pmerioaQ  St^am  Oau^e  ^o.,  BostOQ. 


I  ways  bear 
num  press- 
Y  the  luim- 
allowance. 
pressure, 
in  the  lini- 
I  the  oper- 

ed  nut  at 
I  and  con- 
wing   the 
ling  from 
;  manner, 
shoulder; 
the  scale. 
Bvolving- 
e  cord  to 

efore  use 
me  with 


THE    THOMPSON    IMPROVED    INDICATOR. 

During  his  term  of  office,  Engineer- in-Chief  Charles  H.  Loring, 
U.S.N.,  Chief  of  the  Bureau  of  Steam-Engineering  of  the  Navy  De- 
partment, issued  an  order  directing  the  commandant  of  the  Boston 
Navy-Yard  to  appoint  a  board  to  test  the  Thompson  Improved  Indi- 
cator. The  board  consisted  of  two  officers  of  the  engineer  corps, 
who  made  a  very  thorough  test  and  a  most  favorable  report  as  the 
following  will  show : 

[Copy.] 

United  States  Navy- Yard,  Hoston,  Commandant's  Office, 
March  2,  1885. 
Chief  Engineer  F.  A.  Wilson,  U.  S.  N.,  Xtny-Yard,  Boston. 

Str,  —  The  board  of  which  you  are  senior  member  will  thoroughly  test  the 
Improved  Thompson  Indicator,  submitted  by  the  American  Steam  Ciauge  Com- 
pany, of  36  Chardon  Street,  Hoston,  provided  said  test  is  made  without  cost  to  the 
government. 

Your  report,  which  will  be  in  duplicate,  will  give  a  description  of  the  article, 
and  state  its  advantages  and  disadvantages  for  purposes  under  cognizance  of  the 
Bureau  of  Steam-Engineering,  also  whether  it  is  recommended  for  purchase  and 
use,  as  required  by  Act  approved  July  18,  1861. 

The  report  on  the  Pop  Safety  Yalve  will  also  be  made  in  duplicate,  containing 
a  description  of  the  article,  with  your  recommendation,  etc. 

Very  respectfully, 

(Signed)  O.  C.  BADGER,  Commodore  Commandant. 

[Copy.] 

Navy-Yard,  Boston,  Mass.,  April  10,  1885. 

Sir, — In  obedience  to  the  order  of  the  commandant  dated  March  2,  1885,  we 
have  examined  and  tested  the  Improved  Thompson  Indicator  manufactured  by  the 
American  Steam  Gauge  Company,  and  respectfully  submit  the  following  report : — 

The  features  of  the  instrument  for  which  it  is  designated  the  "  Thompson  Im- 
proved Indicator "  consists  of  one  patented  invention,  a  modification  of  some  of 
its  parts,  and  several  additional  devices. 

They  are  as  follows : — 

1st,  The  improvement  for  which  a  patent  has  been  granted,  is  a  mechanical 
contrivance  for  guiding  the  cord  on  the  paper  cylinder,  the  imparted  motion  being 
from  any  possible  direction.  This  is  effected  by  means  of  a  small  grooved  pulley 
affixed  to  a  bracket  having  a  short  pin,  which  is  fitted  into  a  stand  socket.  The 
bracket,  being  free  to  revolve,  can  be  placed  to  any  required  position,  and  held 
there  by  a  thumb  screw,  which  binds  in  a  small  groove  in  the  pin,  to  prevent  its 
defacement. 

A  hole  through  the  pin  guides  the  cord  smoothly  in  the  groove  of  the  carrier 
disk  for  rotating  the  paper  cylinder.  The  standard  of  the  guiding-pulley  is  on  a 
narrow  disk,  placed  on  a  bolt  underneath  the  base  plate  of  the  paper  cylinder,  and 
is  held  in  position  by  a  wing  nut,  which  enables  the  disk  to  be  readily  adjusted. 


>S 


•^- 


/tmerioaQ  3^^^^  (i^^9?  ^o..  Boetoi^. 


• '^t- 


It  is  apparent  that  the  adjustability  of  the  guiding-pulley  will  give  a  smooth 
and  regular  rotation  to  the  |)a|itr  cylinder,  no  matter  from  what  direction  the  mo- 
tion may  be  imparted.  The  improvement  is  in  keeping  with  the  rest  of  the  details 
of  the  instrument,  and  is  an  invaluable  adjimc  t  where  the  indicator  motion  is  not 
a  )>ermaticnt  fixture.  It  has  no  special  ailvantage,  however,  for  use  on  naval  ves- 
sels, as  the  indicator  motion  is  permanent  and  direct ;  but  it  will  greatly  facilitate 
the  taking  of  cards  from  the  air  and  circulating  pumps. 

2d,  There  is  a  modification  of  the  pencil-carrying  levers,  whereby  they  are 
lightened,  stiffened,  and  harmonized.  Their  principle  and  action,  however,  remain 
unchanged. 

The  working-lever  is  now  a  light  steel  rod  forked  at  either  end,  jointed  at  the 
lower  end  to  the  body  of  the  movable  arm,  and  to  the  main  lever  at  the  upper  end. 
The  length  of  bearing  is  jj  of  an  inch  for  the  lower,  and  jjif  for  the  upper.  The 
old  style  is  a  latticed  plate,  forked  at  either  end,  having  ccji'il  lengths  of  bearing  of 
li^J  of  an  inch.  The  main  of  pencil  lever  and  radius  link  are  of  "drop  "forged 
steel,  the  main  lever  being  bossed  on  either  side,  to  give  greater  stability  of  bearing 
at  the  piston  and  radius-bar  connections,  the  width  of  bearing  being  .12  of  an  inch. 

The  bearing-pins  for  socket  bar  and  piston  connection  are  of  steel,  and  thread- 
ed at  the  end;  those  for  the  radius  bar  are  straight  steel  pins.  The  levers,  forked 
end  of  piston  rod,  and  trunk  connections,  have  been  much  reduced  in  weight ;  and, 
although  reduced  to  a  minimum  of  lightness,  the  superior  connections  will  give 
much  greater  durability. 

The  instrument  without  the  improvements  has  a  quaint,  ungainly,  and  ancient 
look  in  comparison  with  the  newer  design. 

The  weights  of  the  trunk,  piston  rod,  and  levers  of  parallel  motion  are,  31 
grammes  old  design,  and  15  grammes  new  design.  Hence  the  latter  is  31  — 15  x  100 
=  51.6  per  cent,  lighter  than  the  former.  3« 

There  being  no  reduction  in  the  pistons,  and  being  of  equal  weight,  their  weight 
is  not  included  in  the  above. 

3d,  This  improvement  consists  in  the  ratcheting  of  the  base  rim  of  the  paper- 
cylinder  carrier  a  short  distance  on  its  circumference  at  the  limit  of  its  rotation ; 
this,  in  combination  with  a  spring  pawl,  holds  the  cylinder  when  desired,  and  en- 
ables the  user  to  take  off  the  card  and  renew,  without  unhooking  the  cord.  This 
will  save  trouble  and  much  annoyance,  which  will  be  fully  appreciated  by  every 
user  of  the  instrument. 

4th,  This  is  a  device  to  regulate  the  pressure  of  the  pencil  on  the  paper  when 
tracing  a  diagram,  and  consists  of  a  steel  wire  post  riveted  to  the  base  plate  of  the 
paper  cylinder,  and  a  delicate  handle  of  suitable  length  tapped  through  the  movable 
arm,  by  which  means  a  light  line  may  be  always  assured ;  for  with  the  pencil  lightly 
placed  on  the  paper,  and  the  handle  adjusted  against  the  post,  the  heaviest  hand 
must  take  as  fine  a  card  as  a  hand  with  the  most  delicate  touch.  This  will  be  duly 
appreciated  by  those  who  have  to  use  it  in  naval  vessels,  as  the  pencil  can  be  ad- 
justed before  taking  the  instrument  to  the  generally  dim-lighted  and  hot  place  it  is 
used  in. 

The  instrument  has  been  lightened  by  lowering  the  spring  drum,  thus  shorten- 
ing the  spindle ;  also  by  reducing  the  length  and  thickness  of  material  of  the  cylin- 
der. A  cap  is  brazed  on  the  cylinder,  having  a  central  orifice,  through  which  the 
spindle  of  spring  drum  passes  for  strengthening  and  steadying  the  cylinder.     . 

It  has  been  lightened  in  evexy  part  that  would  admit  of  it. 


16 


^fi 


give  a  smooth 
ction  the  nio- 
ot  the  detailH 
niotioii  in  Dot 
on  naval  vcs- 
:atly  facilitate 

ehy  they  are 
wever,  remain 

jointed  at  the 
le  upper  end. 
uiiper.  The 
of  bearing  of 
irop  "  forfied 
ity  of  bearing 
2  of  an  inch. 
,  and  thread- 
evers,  forked 
weight;  and, 
ins  will  give 

and  ancient 
^tion  are,  31 

'  3'  —  '5  X  100 

3> 
their  weight 

the  paper- 
rotation  ; 
:d,  and  en- 
ord.  This 
by  every 

aper  when 
late  of  the 
e  movable 
ncil  lightly 
est  hand 
ill  be  duly 
:an  be  ad- 
place  it  is 

shorten- 
the  cylin- 
t'hich  the 


^ 


w 


m 


f\n\(^r\Qar)  8tean  d^a^R  ^o.,  Bo8t09. 


Tents  were  made  with  several  (llfferrnt  fla««f«  of  cn«ine«,  runging  In  »pecd 
from  so  *"  '5°  icvoliitionH, — no  higlu-r  upecd  could  lie  found,— the  »te«m-|»r«'H<»nre 
varvinn  in  pressure  from  (o  to  lyo  |x>undH. 

I  li«-  tcstH  were  more  than  Hatisfactory,  the  improvements  proving  to  be  real 

and  >t'n»i1ile. 

The  material  used  is  of  the  (inest  (piality,  and  the  workmanship  of  a  high  order. 
All  the  workmen,  havinn  liecn  iiig.igcrl  many  years  in  instrument  making,  arc  reli- 
able and  >kiifiil  in  all  tliu  details.  The  sprin^js  are  tested  by  |)l.»(  ing  tlicm  in  a 
mathiitc  wliit  h  alternately  compresses  and  extends  thcin  1,500  times  in  a  n\iniite ; 
this  "jigging"  process  being  done  for  the  purjicse  of  insnring  the  springs  against 
any  subsetjuenl  set,  orch.mge  in  the  molecules  of  the  nietal  when  in  use. 

The  cylinder  and  piston  are  fitted  to  a  standard  gauge,  anil  are  therefore  inter- 
changeable, as  are  all  parts  of  the  instrument. 
The  whole  is  nickel -plated. 

The  cost  of  the  iiistiunieif  complete  is  eighty-five  dollars. 
The  senior  member  of  the  present  board  was  senior  member  of  a  l)Oard  to  test 
the  Thompson  Indicator  in  1S79.     The  boaril  reported  favorably,  and  rccomtnend- 
ed  its  use  in  the  United  States  Navy,  since  which  time  it  has  been  in  general  use 
in  naval  vessels,  and  is  therefore  well  known 

The  imprcvements  have  added  j;reatly  to  Its  accuracy,  delicacy,  sensitiveness, 
and  durability;  making  the  instrument  about,  if  not  wholly,  as  near  perfection  as  can 
be  obtained:  and  we  have  no  hesitancy  whatever  in  recommending  its  use  in  the 
naval  service. 

Very  respectfully  your  obedient  servants, 
(.Signed)  F.  A.   WILSON, 

JAMKS     HUTTERWORTH, 

CV//<y"  Engimers. 

To   CoMMOlXJRE     I.KWIS    A.    KiMBF.RI.Y,    U.S.N., 

Commaiuiaiit  A'tivy   Wird,  Boston. 


Since  then  valuable  improvements  have  been  made. 


To  substantiate  all  we  claim  for  the  Thompson  Improved  Indica- 
tor, we  respectfully  refer  to  the  following  indovsement  of  parties 
using  them  : — 

TESTIMONIALS. 

.  .  .  In  oliedience  to  your  order  of  Feb.  17,  1879,  we  have  made  a  careful  test 
of  the  Thompson  Indicator,  in  accordance  with  the  order  of  the  Bureau  of  Steam- 
Engineering  of  Feb.  1 5,  1879,  and  respectfully  submit  the  following  report : — 

A  delicate  handle  is  placed  near  the  pencil,  which,  in  combination  with  the  less 
weight  of  moving  parts,  renders  this  instrument  more  sensitive  to  the  touch  when 
applying  the  pencil,  which  is  a  decided  advantage. 


>7 


/tmeri^ar)  Steam  (jau^e  ^o.,  BostoQ. 


'^ 


Ttelirving  that  itiiii  Initriimcnt  in  a  reliable  ami  »en»Uive  one,   we  reiipectfully 
rccottinieiid  iln  ailoptinn  in  the  iiav.il  tcrviic 

(Signet!)     !•    A     W  1 1. SON,  Chit/  Enninttr,  I'.S.X. 

(;.  M.  1,.  MAtCAU  IV,  /'..•»   JHj:iHffr,  U.SuV. 
NV  M     11    1 1 A  l<  K I S,  /'.A.  Inamttr,  V.S.N, 

Tn  CoMMonoRK  (;KMRf;F.  M.   Kansom,  U.  S.  N., 

l't>mm>i>iii<iul  ('.  .V.  .\(ir  1  •  y<tri/,  Hi'stoH, 

NoTi.— Th«  'I'ltiimpviii  Improved  Indicator  hai  been  adopltd  by  the  United  States  Navy  Depart* 
ment  ai  the  ilandard  indiiatur. 


Offick  <if  F.dwari)  r.  Aims  St  •  n,, 

Mii.WAi  KKK,  Wis.,  March  I2,  rS84. 

AmF.RICAN   STKAM   (lAUtJE  CoMI'ANY,  Hostoii,  Mass. 

Gentlemen,— \t\  answer  to  your  intjuiry  about  New  Thoiiips'ui  Indicator,  I  have 
to  say,  that,  as  now  made,  I  consider  it  the  best  in  use,  .uid  have  lonic  to  this  con- 
clusion after  using  all  the  varieties  now  in  the  market. 

Yours  truly, 

KDNVIN    REYNOLDS,  Suptrintendent. 


Ihr 


ilHi'i; 


Ofkkk  of  Pacific  Iron  Works, 

Hrilmiei'ort,  Conn.,  March  14,  1884. 

American  Steam  Ciauge  Comiany. 

Genliemtn, — Ret'  1 1  ing  to  the  Thompson  Improved  Indicator  which  we  purchased 
of  you  last  ycui,  would  say  that  we  have  used  it  upon  a  great  many  high  and  low 
speed  engines,  both  ot  our  own  and  other  l)uilder.s'  manufacture,  and  find  that  it 
gives  perfect  results  and  much  satisfaction;  and,  in  our  opinion,  it  is  the  best  indi- 
cator yet  offered  to  the  public. 

Yours  very  respectfully, 

P.  H.  SKIDMORP:  &  SONS,  Pacific  Iron  Works. 


Mi; 


•V'   '■ 


i 


Delaware-River  Che.micai.  Works, 

20  South  Delaware  Avkni'v,  Pmiladelphia,  Feb.  12,  '884. 

American  Steam  <;auge  Company. 

Gctitlcmin, — Agreeable  to  your  reques  '  \  cI  .e,  as  regards  my  opinion  of 
the  merits  of  the  Thompson  Improved  Indicator,  I  unhesitatingly  reply,  that,  during 
two  years'  practice  with  it  and  other  classes  of  instruments,  I  have  always  found 
the  Thompson  thoroughly  reliable,  even  under  what  is  known  as  high  speeds, — say 
a  thousand  feet  per  minute, — or  locomotive  practice ;  and,  as  long  as  it  continues 
its  present  high  state  of  perfection,  I  shall  consider  it  an  important  adjunct  to  an 
engineer's  '^utfit. 

G.  W.  COOPER,  M.  E. 


fe 


18 


r«  rMpcctfully 


itet  Navy  Depart' 


SuftrintetuUnt. 


Iron  Works. 


w 


/tm^rioar;   8team   (j3<J99  ^o..  Boetoi;. 


i 


Hrrirr  <•>    \\\y  J^K>.^v^  iiv  liMritit'  l.i.i  .   imvp^nx, 
N<».  jiH  Hay  SiKKf  r,  Jm-iKY  «  MY,  N.  j  ,  ►«!».  ^  iJWy 

II.    K.    MnoHK,  \,^<l^i 

Suft riH(,Hiltnt  .Im'-^tt'im  Stt,tm  Gaut,'/  ('iimfum',  Most.m,  JUm*. 
I  am  (IflJuhti      vith  the    Niw   I  hom|>!»<>n   Impnutfl  Indicjlor  vcn*  recently  fur> 
iii»lu(l  mc.      I  lie   111  w  form  of    paper  tlrndi  t-n^l'lc*   mt-  lo  tati-  •Jntx'nimj  uf' !•' tit 
kmuittj  moliilioHM  per  iiu'muc,  wilhimt  alfccling  ii)  Any  senile  thrir  accuracy.      I  he 
imprnvrd  p.ir.tllcl  iiioiiui)  i.,  ,\\\  tli.it  coiilil  'h-  (jesirtil.     At  HUr  time  i  had  eight  in 
(li(  aiors  of  (lilfcmit  m.iiiiifai  luri',  i///./  h^i^nd  I'v  >t<mf<itrisoii,  th,u  thi    I'/iomf'i''"  'i<i 
I,  ts  /(lulls  than  any  of  tlu-  olluts ;  therefore  I  (all  it  my  *.ivo«ilf,  iiHiiig  it  on  all  <>» 
I  aHioii>»  where  prci  i<ii(iii  is  iiectftsarv.     A  N'ew    Thomiis.di   Iiv<liiator  ohould  hv  .ill 
Illeall^  he  pl.ited  in  every  engine-room,  where  its  juilit  ioim  ii.Hf  will  readily  pro^  it 
a  reliahlc  uhcck  on  the  cual  pile. 

KeHpi'i.'trully  yours, 

L.    h  .    I . \' .\ I •:,  SiifnintrnJiiil. 


OFf  I'  K   nh    llIK    Kl.lNI'    .Mril^, 
F/Vl.!    KiVK.R,  Mass  ,  Kcli.  ;,.  1S.S5. 

AMKRICAN    .STF.AM   ("»AIT«;K   CuMPANV.  />'(i.r/iW,  iJ/».*i. 

(iiiits, —  \"()ur  favor  of  thi-  ^ist  of  January,  rc<(iicsli  ;  a  statement  of  tiie  facts 
concerning  the  exchange  of  our  (  ro.sl)y  Indicators  for  \  le  Ihompson  Improved  at 
our  mills,  is  received  and  noted. 

Replying,  will  say  that  some  time  ago  we  purchased,  in  good  faith,  a  pair  of 
Crosby  Indicators,  of  the  kind  known  as  N'o.  2. 

These  instruments,  from  the  first,  were  a  source  of  trouble  to  us.  The  diagrams 
woukl  show  a  loss,  from  boiler  pressure,  of  seven  to  nine  \<  uiuis,  which  no  ad|ii»t- 
incnt  of  the  valve  of  our  engine  would  remedy.  The  ari.-igemcnt  for  changing 
springs  in  the  Crosby  instruments  is  complicated,  and  tci  'Us  to  perform.  The 
adjustment  re(|uiied  in  maintaining  a  |>ropcr  height  of  pi  ;k  il,  especially  for  con- 
densing-engines,  like  oursj  is  so  fine  ami  so  easily  disarranged,  that  we  think,  every 
thing  considered,  the  instrument  unfit  for  ordinary  everyday  i.se. 

With  these  facts  in  mind,  we  wrote  you,  reipicsting  a  jiair  of  Thompson  Improved 
Indicators  for  trial,  with  your  best  terms  for  the  e.xchanKC. 

We  have  had  the  I'liompstin  Indicators  three  or  four  weeks  ami  are  more  than 
|ileased  with  them. 

The  diagrams  with  these  instruments  show  a  difference  of  01  Iv  oiif  pound  from 
boiler  pressure,  and  a  very  fine  distribution  of  steam,  and  thiswii  c>ut  any  alteration 
in  the  valves  of  our  engines.  The  arrangement  in  these  instrmrients  for  changing 
springs  is  simple,  readily  understood,  and  cpiickly  performed  ;  and  the  height  of 
pencil,  once  adjusted,  is  always  the  same.  The  swivel  jnilley  for  guiding  the  cord 
deserves  special  conimendation,  and  we  unhesitatingly  pronounce  the  Thompson 
Improveil  Indicator  to  be  the  best  indicator  for  our  use  we  have  \  •-•t  seen;  and  we 
enclose  check  to  balance  our  account.     I'iease  acknowledge  the  same,  and  oblige 

Vours  respectfully, 

W.M.  .S.   I'OTTKR,  Treasurer. 


% 


19 


3 


pm^rieap  Steam  Cjaii^^  ^o.,  BostOQ. 


^ 


ni! 


Boston,  June  r,  1884. 
American  Steam  Gauce  Company,  ^w/<jw,  ^//.r.r. 

GiHtlemtii,  —  Havin}^  used  tlu-  'I'liompson  Improved  Indicator  on  many  different 
styles  of  engines,  at  s|)ec(ls  varying  fioin  seventeen  revolutions  up  to  three  hundred 
and  fifty,  with  marked  success,  I  have  no  hesitation  in  saying  that  I  consider  the 
Thompson  Improved  Indicator  a  very  valuable  adjunct  to  an  engine's  or  engineer's 
outfit. 

Yours  very  truly, 

C.   n.  ATKINS,    With  llw  Kncnvli's  Sti'am-Punip  Works. 


OlTTCE   OK    ('.    A.    SeI.KY, 

Room  53,  Gii.iiM,AN  lii.oi  K,  St.  Pahi.,  Minn.,  March  14,  1884. 
American  Steam  Gauck  Company,  j6  Chardon  Street,  lioston,  Muss. 

Gentlemen,  —  I  wish  to  indorse  tlic  Thompson  Im])roved  Indicator  as  a  reliable, 
true  instrument,  and  have  been  perfectly  satisfied  with  its  convenience  of  application 
to  any  situation.  I  have  used  it  and  others  on  locomotives,  and  high  and  low  speed 
engines,  with  other  indicators,  and  have  never  had  cause  to  doubt  it.     I  am,  sirs. 

Yours  truly, 

C.  A.  SELEY. 


Philadelphia,  July  22,  1884. 
American  Steam  Gauce  Company,  j^cjA'/i, /I/I/w. 

Gents,  —  The  Thompson  Indicator  which  you  furnished  me  has  given  nie  good 
satisfaction.  I  have  used  it  frequently  u|)on  high-speed  engines,  with  indicators  of 
other  makers,  and  have  not  yet  had  occasion  to  regret  the  choice  which  I  made 
when  I  selected  yours. 

Respectfully  yours, 

II.  L.  BUTLER. 

Office  of  Thomas  Pray,  Jun., 

Boston,  Mass.,  July  23,  1884. 
H.  K.  Moore,  Superintendent  Ameriean  Gaui^e  Company,  Boston,  Muss. 

In  reply  to  your  inquiry,  I  do  not,  have  not,  and  shall  not,  make  use  of  any  indi- 
cator except  the  Thompson  Improved,  of  your  make,  in  my  work  on  adjusting, 
indicating,  etc.,  until  I  find  something  better.  I  have  tried  them  all,  and  use 
none  but  Thompson's  in  my  practice.  The  little  Fellow  No.  2  is  the  best  high-speed 
indicator  now  out.  Have  used  it  at  six  hundred  and  forty  per  minute.  And  your 
springs  and  indicators,  as  now  made,  are  the  best  I  have  ever  seen  or  used. 

Respectfully, 

THOS.  PRAY,  Jun. 

Calumet  and  Hecla  Mining  Company, 

OFFICt   OF   CONSULTIN(i   ENGINEER,    C AMHRIDGEPOR T,    MasS.,  Jan.  24,  1885. 

American  Steam  Gauge  Com\'anv,j6  C/iurdon  Street,  Boston. 

Gents,  —  In  reply  to  your  favor  of  the  23d,  I  am  pleased  to  state  that  I  regard 


•h* 


20 


rump  Works. 


%»^ 
^ 


/^ff^ericap  3^^^^   (j^^^^  ^o.,  BostOQ. 


'% 


your  Improved  Thompson  Indicator  as  the  best  instrument  of  its  kind  extant,  and 
invariably  order  it  for  l)oth  fast  and  sl<nv  speed  engines.  It  is  the  only  instrument 
which  has  proved  satisfactory  on  our  steam  stamp. 

Yours  truly, 

K.  IJ.  I.EAVITT,  Ji'N.,  Consulting'  l\n}:;inier. 


Stevens  Institute  ok  Technolocy, 
IIoHOKEN,  N.  J.,  May  28,  1884. 
A.merican  Steam  Gatge  Company,  Boston,  Mass. 

Gentlemen, — \ours  of  the  27th  is  received.  In  reply  I  take  pleasure  in  saying  that 
the  pair  of  Thompson  Indicators  to  which  you  refer  are  in  frequent  use  in  the 
work  of  the  mechanical  laboratory  of  the  Stevens  Institute  of  Technology,  and 
are  a  very  iaii)ortant  i)art  of  its  outfit.  The  recent  changes  made  in  the  construction 
of  the  instrument,  with  a  view  to  adapting  it  to  use  on  "high-speed  engines," 
are,  in  my  opinion,  very  decided  improvements;  and  the  new  arrangement  for 
leading  off  the  cord  from  the  paper  cylinder  is  as  handy  as  it  is  neat  and  ingenious. 
I  am  very  much  pleased  with  these  improvements  upon  what  was  originally  a 
vary  excellent  instrument. 

The  steam-engine  indicator  is  so  essential  a  part  of  every  engineer's  outfit,  that 
these  steps  in  the  direction  of  securing  precision  in  its  work  are  of  special  interest 
to  every  member  of  the  profession. 

Very  respectfully  yours, 

K.  H.  THURSTON. 


Office  ok  National  Association  ok  Stationary  Knijinekrs, 
DtTRoi  r,  Mich.,  May  30,  1884. 
American  Steam  Gauge  Company,  Hoslon,  Mass. 

Gentlemen, —  Replying  to  yours  of  the  27th  inst.,  relative  to  the  usefulness  of 
the  indicator  in  general  as  an  engineer's  outfit,  would  say  every  man  who  aspires 
t)  the  calling  of  an  engineer  should  own  one,  and  use  it.  Its  reading,  combined 
with  a  little  brain  \vorI<,  will  save  engineers  and  firemen  many  hours  of  manual 
labor,  besides,  in  many  cases,  a  source  of  profit  to  the  employer;  and  I  funily 
believe,  that,  when  its  benefits  are  more  widely  known  and  ajipreciated,  employers 
will  only  engage  men  as  engineers  who  are  versed  i'l  indicator  practice,  and  will 
remunerate  them  accordingly. 

Respectfully  yours, 

A.  M.  DAW. 


The  Skenandoa  C(jtton  Company, 
I'  I ICA,  N.  v.,  .May  27,  1S84. 
A.MiKicw   SrisM  (iMc.F.  COMPANY,  H.    K.  ^]in>Rr.,  Sn/\ri/ite//(le/it. 

J  >e<ir  .Sir, —  In  reply  to  yours  of  the  24th,  have  t)  say  that  the  Thomiisnn  Iin- 
jiroved  Indicator  and  I'laninieter,  jjurchased  of  you  last  Nuvember,  have  been  in 
(lailv  use  since.  Having  instructed  my  engineer  how  to  use  them  and  ailjust  the 
valvus,  he  is  re(iu':red  to  take  cards  with  the  indicator  four  times  each  day,  work 
thciH  up,  and  report  the  average  horse-jxjwer,  ])ou!uls  of  coal  used,  pounds  of  coal 


-4-0 


21 


i  !!^ 


I!  -' 


^ 


%^:t- 


f\m(^T'Kaq  St^am  QaiK^e  <5o.,  Bostop. 


^ 


l)i;r  horse-power  per  hour,  and  the  cost  of  each  horse-power  per  hour  and  report  to 
the  otificc  at  the  end  of  each  week. 

I  enclose  cards  taken  during  the  last  five  months,  to  show  whether  the  valves 
are  properly  adjusted  or  not. 

I  believe  both  instruments  should  be  furnished  to  the  engine-room  as  a  part  of 
its  outfit,  and  the  engineer  instructed  how  to  use  them,  especially  for  engines  of  a 
hundred  or  more  Injrse-jjower. 

My  engineer  and  fireman  have  become  as  much  interested  in  the  economical 
working  of  the  engine  as  they  would  if  they  had  to  furnish  the  coal  themselves. 
The  engineer  has  used  the  indicator  on  a  neighbor's  engine,  making  two  hundred 
and  twenty  revolutions  per  minute  ;  and  the  cards  show  clear  and  distinct  lines,  as 
on  slow-running  engines. 

I  am  trying  four  different  kinds  of  soft  coal,  and  expect  to  be  able  to  tell  the 
relative  value  of  the  coals  by  the  indicator. 

Yours  truly, 

I.   R.  SCOTT,  Superintendent. 

....  In  response,  I  would  say  that  the  Thompson  Indicator  is  the  most  precise 
instrument  of  its  kind  I  have  any  knowledge  of ...  . 

With  the  Thomjjson  Indicator  I  have  f)btaincd  diagrams  from  locomotive  engines 

at  speeds  varying  between  two  hundred  and  three  hundred  revolutions  per  minute 

and  have  found  the  lines  as  regular  and  precise  as  at  speeds  of  fifty  to  a  hundred 

with  same  engine  .... 

JOHN'  W.  HILL,  Consulting  Engineer. 

Cincinnati,  O. 

Amkrican  Steam  Gauge  Co'siv\s\,j6  C/iivdon  Street,  Hos/on,  Mass. 

(ienl/eineji, —  In  reply  to  yours  of  the  J7th  would  say  that  we  keep  in  constant 
use  from  this  ofticc  six  of  the  Thompson  Indicators,  some  of  which  have  been 
rebuilt  from  the  Richards  Instrument,  with  greatly  inrproved  results.  As  our  prac- 
tice is  mostly  with  high-sjieed  work,  our  insirnnients  are  severely  tested ;  as  for 
instance,  equalizing  the  valve  motion  at  two  hundred  revolutions  to  cut-off  at  one 
per  eent.  of  the  stroke  under  eighty  pounds  of  steam.  The  Thompson  Indicator 
performs  this  service /iv/;'!//)',  which  cannot  be  said  of  any  other  instrument  within 
our  knowledge. 

Vours  respectfully, 

W.M.  LEK  CHURCH. 
Nkw  York. 

OFFICK    111-     UrcKKVK    I'.NC.INK    COMl'ANV, 

S AI.KM,  ( ).,   Feb.   3,    iS.Sq. 
A.MKRicAN  Steam  Oauc.e  Company,  j>6  Churdon  Street,  J^os/on,  Miiss. 

(Jentlenien, —  We  have  had  several  of  the  Thompson  Indicators  in  constant  use 
ever  since  their  first  introduction,  applying  them  to  engines  of  all  sizes  and  speeds, 
and  working  under  all  pressures  and  grades  of  expansion  usuallv  met  with  in 
engineering  practice,  and  have  never  met  with  a  single  instance  in  which  the  amount 
of  vibration  was  sutiicieiit  to  impair  the  value  of  the  diagram  |)roduced.  Previous 
to  its  introduction,  it  was  not  an  uncommon  thing  in  our  experience,  in  indicating 


^1: 

mi 


I 


?• 


^ 


ir  and  report  to 

;ther  the  valves 

om  as  a  part  of 
or  engines  of  a 

the  economical 
)al  themselves, 
g  two  hundred 
istinct  lines,  as 

ible  to  tell  the 

Superintendent. 

e  most  precise 

motive  engines 
ins  per  minute 
y  to  a  hundred 

tint:;  lini^'ineer. 


iss. 

in  constant 
h  have  been 
As  our  prac- 
ested ;  as  for 
cut-off  at  one 
son  Indicator 
unient  within 


cnuRcir. 


K    t'OMPANV, 

SSo. 

i'S. 

constant  use 
and  speeds, 

net  with  in 
the  amount 

i.     I'revious 

1  indicating 


f\n\qr\^aq  Steam  Qau^(^  Qo.,  Bo5t09. 


engines  running  at  high  m  moderately  high  rotative  speed,  and  woiking  expansively 
under  good  pressure,  to  encounter  such  excessive  vibration  as  to  render  the  results 
worthless;  and,  independently  of  the  (picstion  of  vibration,  we  have  found  that  its 
other  merits  (which  will  I)e  a|>parent  to  engineers  of  any  degree  of  familiarity  with 
indicators)  are  such  as  to  give  it  a  decided  superiority  under  all  circumstances. 

The  marvellous  delicacy  and  perfection  of  its  action  cannot  be  better  illustrated 
than  by  the  accompanying  cut,  which  represents  a  friction  card  taken  by  ourselves 
from  one  of  our  16  by  32  inch  cut-off  condensing  engines.  It  represents  conditions 
under  which  distortion  from  vibration  would  naturally  be  very  excessive  with  the 
most  imjjroved  instrument. 

The  card  is  one  of  a  number  taken  while  adjusting  the  condenser,  and  stopping 
air  leaks.  Speed  of  engine,  ninety  revolutions  per  minute;  scale,  forty  pounds- 
Five-inch  throttle  open. 

Very  truly,  etc., 

HUCKLVE  KNGINE  COMPANY, 
I'ER  Ji)i;i.  Sharp,  President. 


Oi-'i'KE  OF  Frank  H.   I'ond,  i\\  North  F.ichth  Sikkf.t, 

."^  \.   I.oi'is,  Feb.  3,   I  SSo. 

American  Steam  Gait.e  (.'omi' any,  j'i')  ( '//,/r./ri// ^a,  HoUou.  Mass. 

diUtUiitiii,  —  \'our  faviii  of  the  Jijtii  is  at  hand.      In   re])lv.  would  sav  rei;ardin^; 

the   Thompson  Iiuiicator,  having  used  botli  that  and  tlie  kiiliai(l>.  I  ( unsidcr  it  far 

supeiior  in  sensitiveness  and  tMse  of   motion,  and  well    adapted  to   be  useii  on  the 

ilMiek-uinning  engines  of  the  present  day.     There  have  been  many  improvements 

embodied  in   tiie    Thompson  whi(  h   e,\|)erience   has  shown  to  be  necessary,  and  it 

seems  to  meet  all  jiractieal  recjuirements. 

\ours  trulv, 

FKA.NK    H.    I'OM). 


ti 


23 


#t; 


hi' 
I  ii 


1    !:-!nl 


W^ 


fi(i\er\QaT)  St^am  Cau^^  Qo.,  BostOQ. 


"^ 


St.  Louis  Gas-Light  Company,  No.  511  Olive  Street. 

St.  Loris,  March  21,  1882. 

American  Steam  (Iauc.e  Qo}av\h\,j6  Oianion  Strtft,  Bostim,  Afuss. 

Gentlemen,—  Please  forward  by  express,  C.  (J.  D.,  one  No.  12  and  one  No.  20 

spring  for  Thompson  Indicator,  No.  240. 

Have  been  using  your  indicator  for  over  a  year,  and  consider  it  a  beautiful 

instrument,  delicate  and  fine  in  its  action,  and  a  pleasure  to  work  with. 

If  you  have  no  No.  12,  send  No.  16  instead. 

Yours  truly, 

JOHN   SOBOLEWSKI. 

Cincinnati,  Ohio,  Mar.  8,  1889. 
American  Steam  Gauce  Co.,  Boston. 

Gentlemen,  —  I  have  used  Thompson  Steam  Engine  Indicators  for  fifteen  years, 
in  fact,  ever  since  they  were  first  introduced,  and  have  at  all  times  and  under  all 
conditions  of  engine  service,  found  them  entirely  reliable. 

In  all  my  experience  I  have  never  had  occasion  to  complain  of  the  manner  in 
which  they  performed,  and  if  I  were  buying  Indicators  today  I  should  buy  the 
Thompson. 

I  do  not  know  that  I  can  express  my  regard  for  these  invaluable  instruments  in 

any  stronger  language. 

Very  respectfully, 

JOHN  W.  HILL,  C.  E. 

Calumet  &  Hecla  Mining  Company. 

Office  of  the  Consultinc,  Engineer,  Camuriugeport,  Mass.,  Mar.  6,  1889. 
American  Steam  Gauge  Co.,  j6  Chardon  Street,  Boston. 

Gentlemen, —  I   have  to  say  that  after  quite  an  extensive  use  of  the  Thompson 

Indicator,  I  am  persuaded  that  it  is  a  most  excellent  instrument,  and  that  my 

confidence   in   the  same   is  proven   by  the  orders  from  time   to  time  sent  your 

company. 

Vours  truly, 

E.  D.  LEAVITT,  Jr.,  Consulting  Engineer. 

Sibley  College,  Cornell  University. 

Ithaca,  N.  V.,  March  12th,  1889. 
Gentlcnun,  —  It  gives  me  great  pleasure  to  say  that  the  instruments  sent  us  have 
proved  to  be  of  most  excellent  quality,  and  so  far  as  our  work  has  given  oppor- 
tunity to  judge,  of  great  .iccuracy.     \Vc  have  used  them  on  all  kinds  of  work,  and 
at  speeds  of  rotation  uj)  to  300,  and  have  found  them  capable  of  doing  admirably. 

'I'lie  finish  is  excellent  ai  d  the  sizes  and  fits  are  all  that  could  be  desired. 
They  have  been  very  useful,  both  in  class  work  and  in  making  engine  trials,  and 
eminently  satisfactory  in  all  respects.  We  have  had  no  dititkulties  with  them 
except  such  as  have  come  from  their  use  by  inexperienced  hands. 

When  used  for  instruction  an  occasional  accident  is  to  be  expected.  They  have 
withstood  such  injuries  quite  as  well  as  we  ought  to  expect,  and  have  done  more 
work  and  better  work,  even  in  such  hands,  than  I  had  supposed  possible. 

Very  respectfully  yours, 

R.    II.  THURSTON,  Director. 


% 


24 


Oi.ivE  Street. 

Afiiss. 

and  one  No.  ao 

!r  it  a  beautiful 
ritii. 


OBOLEWSKI. 
o,  Mar.  8,  1889. 

)r  fifteen  years, 
s  and  under  all 

the  manner  in 
ihould  buy  the 

instruments  in 


HILL,  C.  E. 


Mar.  6,  1889. 

he  Thompson 
and  that  my 
ne  sent  your 


«?■  En^neer, 


h  1 2th,  1889. 
sent  us  have 
;iven  oppor- 
>f  work,  and 
idmirably. 

be  desired. 
2  trials,  and 

with   them 

They  have 
done  more 


,  Director. 


sm 


/Imerieai}  St^am  (^auQe  $0.,  Bostoi). 


"^ 


Enw. 


r.  Allis  &  Co.,  Rkliance  Works, 

MiLWAiKEK,  Wis.,  Mar.  14,  iS.Sg. 
Amkrkan  Steam  riAU<;K  Co.,  Boston,  Moss. 

iieiitltmeii, —  I  have  used  all  the  prominent  makes  of  Indicators,  but  verv'  much 
prefer  the  Thompson,  and  believe  it  has  more  good  points  and  less  faults  than  any 
other  instrument  made.  The  easy  changing  of  springs,  good  leading  pulley  for  the 
curd,  general  convenience  in  handling,  and  last,  but  certainly  not  least,  its  ability  to 
stand  abuse,  are  some  of  the  features  that  commend  it  to  the  practical  engineer. 

Yours  truly, 

IRVING  H.  REYNOLDS. 


ii>- 


PRICES    OK    THOMPSON    IMPROVED    INDICATOR    AN1> 
EXTRA  FIXTURES. 

Thompson  Indicator  complete,  with  one  spring,  in  the  instrument,  one 
scale,  two  cocks,  all  necessary  wrenches  to  use  on  the  instrument, 
one  screw-drivei,  one  bottle  watch-oil,  and  Pray's  "Twenty  Years 
with  the  Indicator,"  all  enclosed  in  a  neat  mahogany  box 

Thompson  Indicator,  with  the  above  fi.xturcs,  and  nickel-plated 

Extra  Piston,  J^-in.  area 


"      Springs 

"      Box-wood  Scales 

"      Steel  Scales 

"      Cocks 

"      Elbows 
Three-way  Cock 
Single  Carrying-Pulley 
Double  " 

Parallel  Rule 
Reducing- Pulley 
Clamps 
Metallic  Cards 
Common  Cards 
Detent  Motion 
Pantograjih 
Planimeter  , 


each 


per  thousand 


$85.00 
88.00 
10.00 
5.00 

•SO 
1.50 

2-75 
2.50 
6.00 
.60 
1.20 
7.00 

25-00 
3.00 

15.00 

7-50 

3.00 

10.00 

1  vOO 


.S  TEE L    INI) ICA  TOR. 

The  regular  Thompson  Intlicator  is  made  of  Brass  ahiiost 
entirely,  and  would  not  stand  the  action  of  the  ammonia  used  in 
Ice  or  Refrigerating  Machines.  For  these  machines  we  make 
Thompson  Improved  Indicators  all  steel,  to  withstand  the  action  of 
the  ammonia. 


Price,  all  complete,  with  fi.xtufLS  as  above  cuumerateil  in  price-list 


$  1 40.00 


Sw? 


.\ 


:/"* 


pm^rioai)  Steam  Oau^^  ^o.,  Boetop. 


TO    ENGINEERS. 

Every  man  aspiring  to  the  calling  of  an  engineer  should  own 
and  use  an  Indicator  ;  and,  although  the  subject  may  at  first  seem 
too  deep,  it  is  nevertheless  true,  that  any  engineer  can,  with  the 
assistance  of  the  book  of  instructions  sent  with  each  instrument, 
learn  to  use  the  indicator  with  satisfactory  results  in  a  short  time. 

To  engineers  we  can  allow  special  tcrtus^  and  will  furnislv 
particulars  upon  application.  We  solicit  correspondence  on  the 
subject. 

The  following  parties  use  the  Thompson  Improved  Indicator ; 
also  a  great  many  others  who  have  procured  the  instruments  of  our 
agents : — 

Alex.  Pollock,  Engineer New  York. 

John  Roach  &  Son,  Steamship  Guilders        .  .     New  York. 

Charles  W.  CoiJeland,  Consulting  Kngineer.  .  .  New  York. 
William  Lee  C!hurch,  Consulting  Engineer  .  .  .  New  York. 
Henry  VV.  Hulkley,  Consulting  Engineer      .        .        .     New  York. 

A.  &  F.  Hrown,  Engineers New  York. 

H.  A.  Rogers,  Engineer  ......     New  \'ork. 

S.  R.  Kirby,  Engineer New  York. 

Delamater  Iron  \Vorks,  Ste.imship  Guilders  .  .  New  York. 
James  Hoggs  &  Co.,  Engineers  .....  New  York. 
William  Cramp  &  Sons,  Steamship  Huilders        .        .     Philadelphia,  Penn. 

T.  H.  Hickerton  &  Co.,  IJigincers Philadelphia,  Penn. 

Harlan  «S:  Ilollingsworth  Company,  Steamship  l!uilders,Wilmington,  Del. 
The  Pusey  &  Jones  Company,  Steamshij)  Puiiders      .     Wilmington,  Del. 
Ilerreshot^  Manufacturing  C()m])any,  Engineers  .         .     liristol,  R.  \. 
M.  C.  Pignall,  Mechanical  luigineer      .         .         .         .St.  Louis,  Mo. 
F"rank  11.  Pond,  Mechanical  Engineer  .        .        .        .St.  Louis,  Mo. 

Sanford  &  Covel Fall  River,  Mass. 

W.  F.  Sherman,  Mechanical  Engineer  ....     Lawrence,  Mass. 
Whittier  Machine  C"ompany,  Engine  Puilders       .         .     Poston,  Mass. 
Washburn    &   Moen   Manufacturing  Company,   Wire 

Manufacturers Worcester,  Mass. 

W.  C.  Joiinson,  Engineer Fitchburg,  Mass. 

Schofield  Iron  Works     ......     Macon,  (Ja. 

A twood  &  McCaffrey,  Engineers Pittsburgh,  Penn. 

H.  IL  Westinghouse,  Engineer Pittsburgh,  Penn. 

Hill,  Clarke  &  Co Boston,  M.iss. 

Henry  L.  Einstein J5ound  Brook,  N.  J. 

Renter  &  Mallory,  Engineers Paltiniore,  Md. 

United  States  Navy  Department Washington,  D.  C. 


26 


A  \ 


should  own 
at  first  seem 
'">  with  the 

instrument, 
loit  time, 
vill  furnish 
nee  on  the 

Indicator ; 
ents  of  our 


^BB^ 

i^           flm^riGa9  8tean\  Q^ti^^  ^o.,  Bo8t09. 

11 

John  W.  inil,  Consulting  Engineer     ....     Cincinnati,  O. 

1 

CiOulds  &  Ostrander,  Fngineers 
North  Star  Iron  Works 

St.  Louis,  Mo. 
Minneapolis,  Minn. 

Lane  &  Hodley  Company 

Cincinnati,  O. 

Conant  Thread  (ompany 

(jrand  Trunk  Kailroad'of  Canada 

Pawtucket,  R.  L 
Montreal. 

Frazer  &  Chalmers,  Kngineers 

Chicago,  III. 

Holly  Manufacturing  Company,  Kngineeis 
Portland  Company,  Locomotive  Builders 
Pennsylvania  Railroad  .... 

Lockport,  N.  Y. 
Portland,  Me. 
Philadelphia,  Penn. 

F.  1).  Leavitt,  jun.,  Mechanical  Fngineer 
1       William  A.  Ilarri.s,  Engine  Builder 

Cambridgeport,  Mass. 
Providence,  R.  I. 

1      (Jeorge  T.  Mcl.authlin  &  Co. 

1       Randolph  &  Co 

'.       (ieorge  S.  Beers,  Engineer    . 
Parke  &  Lacey,  Engineers 
W.  T.  Garratt  &  Co.,  Engineers    . 
Edward  P.  Allis  &  Co.  . 

Boston,  Mass. 
.    Central  City,  Col. 
.     New  Milford,  Conn. 

San  Francisco,  Cal. 

San  Francisco,  Cal. 

Milwaukee,  Wis. 

Woodbury,  Booth  &  Pryor,  Engineers        , . 
Frank  E.  Kirbv,  Mechanical  Engineer 

Rochester,  N.  V. 
Detroit.  Mich. 

Atlas  Engine  Works,  Engine  Builders 
J.  A.  Lauder,  Su])t.  M.  P.  O.  C.  R.  R. 
Calumet  &  IFecla  Mining  Company     . 
F.  R.  Redpath,  Consulting  Engineer    . 

Indianapolis,  Ind. 
Boston,  Mass. 
Calumet,  Mich. 
Montreal,  Can. 

Con.stant  Mecse,  Sugar  Refining  . 

Robert  Wetherill  &  Co. 
[       American  Rubber  Company 

Robert  Whitehill   .         .     '  . 

Warden  &"  Hinckley      .... 

American  Tool  and  NLichine  Company 

Cincinnati  Water  Works 

R.  O.  Moorhouse 

Nonantum  Worsted  C"ompany, 

John  IL  Mcdowan  Company 

Hartford  Engineering  Company   . 

Natchez  Cotton  Mills 

J       Eliot  B.  Mayo 

California  Paper  Company    . 
.    Pacific  Mills  .        .         .        . 

Brush  Electric  C!ompany 

W.  Bingham  &  Co 

Rand  Drill  Company     .... 

Massachusetts  State  Prison  . 

Denver  Foundry  and  Machine  Company 

Erie  and  Wtstern  Transportation  Compan; 

\'ale  Lock  Manufacturing  Company     . 

Utica  Steam  Cotton  Mills    . 

George  S.  King 

Cambria  Iron  Company 

r 

San  Francisco,  Cal. 
Chester,  Penn. 
Cambridge,  Mass. 
Newburg,  N.  V. 
Chicago,  111. 
Boston,  Mass. 
Cincinnati,  O. 
Philadelphia,  Penn. 
Newton,  Mass. 
Cincinnati,  C). 
Hartford,  Conn. 
Natchez,  Miss. 
Boston,  Mass. 
San  Francisco,  Cal. 
Lawrence,  ^L'lss. 
Cleveland,  (). 
Cleveland,  O. 
New  York. 
Concord,  Mass. 
Denver,  Col. 
Buffalo,  \.  v. 
Stamford,  Conn. 
Utica,  N.  Y. 
Pittsburgh,  Penn. 
Johnstown,  Penn. 

i 

1 
i 

% 

^ 
^ 

^ — — 1 

flm^rioap  Steart^  Cjau^^  ^o.,  Bo8to9. 


C.  Stewart  &  Son  , 

William  Berwick    . 

S.  A.  Goodwin 

Morton,  Kced  &  Co. 

.\(/,^V<'  tSr»  Kiump    , 

Thomas  Shaw 

Ilailowell  Cotton  Manufacturing  Company 

St.  Paul  and  Sioux  City  Railroad  Company 

Chicago,  Rock  Island  and  Pacific  Railroad  Com 

John  (jauge    .... 

University  of  Minnesota 

University  of  Wisconsin 

Stephens  Institute 

Massachusetts  Institute  of  Technology 

Cornell  University 

R.  F.  Power 

J.  W.  Hirkett  .... 

Boston  Rubber  Shoe  Company     . 

J.  Firmenich 

Crane  Iron  Company     . 
Exeter  Machine  Works 
St.  Louis  Gas-Light  Company 
North  River  Iron  Works 
Arlington  Mills      .        .        -        . 
Utica  Steam  Gauge  Company 
Cleveland  Rolling-Mill  Company 
I).  P.  Stewart         .... 
Buffalo  Grape  Sugar  Co. 
Otto  C.  Woolf        .... 
Whittenton  Manufacturing  Company 
Otis  Iron  and  Steel  C  ompany 
Bass  Foundry  and  Machine  Comjjany 
M.  F.  Pennywell    .... 
Henry  Parsons       .... 
H.  S.  Robinson     .... 

Globe  Mill 

Stei)hen  Sanford    .... 

G.  Hall,  jun 

Thomas  Pray,  jun. 

Door,  Sash,  and  Lumber  Company 

Bay  State  Iron  Company 

Knc^wles  .Steam-Pump  Works 

George  I  >.  Putnam  \  Co. 

N.  E.  Weston  Electric  Light  Co. 

E.  L.  Sanford         .... 

Tilestou  <S:  Hollingsworth 

George  F.  lilake  Manufacturing  Company 

E.  B.  Vannevar 

The  Lockwood  Manufacturing  Company 


pany 


Worcester,  Mass. 
Hill  (Jrove,  R.  I. 
Philadel|)hia,  Penn. 
Baltimore,  Md. 
llamburgy  Germany. 
I'hiladelphia,  Penn. 
Ilailowell,  Me. 
Shakojiee,  Minn. 
Chicago,  111. 
Washington,  D.  C. 
Minneapolis,  Minn. 
Madison,  Wis. 
Hoboken,  N.  J. 
Boston,  Mass. 
Ithaca,  N.  Y. 
Leadville,  Col. 
Brooklyn,  N.  Y. 
Maiden,  Mass. 
Buffalo,  N.  Y. 
Catasauqua,  Penn. 
Exeter,  N.  IL 
St.  Louis,  Mo. 
New  York. 
Lawrence,  Mass. 
Utica,  N.  Y. 
Cleveland,  O. 
Buffalo,  N.  Y. 
Buffalo,  N.  Y. 
Philadelphia,  Penn. 
Taunton,  Mass. 
Cleveland,  O. 
Fort  Wayne,  Ind. 
Racine,  Wis. 
Newark,  N.  J. 
Boston,  Mass. 
Woonsocket,  R.  I. 
Amsterdam,  N.  Y. 
So.  Willington,  Conn. 
Boston,  Mass. 
Cleveland,  O. 
Boston,  .Mass. 
Boston,  Mass. 
Boston,  Mass. 
Boston,  Mass. 
Boston,  Mass. 
Boston,  Mass. 
Boston,  Mass. 
Boston,  Mass. 
Boston,  Mass. 


28 


# 


•  r*                                                                                             ■                * 

V.i 

f*^           /Jmeri^ap  Steam  QBis^e  ^o.,  Bo8to9. 

• 

% 

George  K.  Paul  &  Co P  "ton,  Mass. 

Pacific  <iu.in<i  (Onipany 

I        .m,  Mass. 

llrush  Kicctric  light  Company 

Boston,  Mass. 

VV.  K.  Crane 

Boston,  Mass. 

O.  A.  cSi  K.  M.  Ames      .... 

Boston,  Mass. 

Kureka  Silk  Manufacturing  Comjiany  . 

Boston,  Mass. 

John  J,  Kay 

Boston,  .\tass. 

lloiiinj;sw<)rth  &  Whitney  Company    . 

Boston,  Mass. 

Walworth  Manufacturing  Company     . 

Boston,  Mass. 

Palmer,  Parker  iv  Co 

Boston,  Mass. 

West  liiiylstun  Manufacturing  Company 

Oakdale,  Mass. 

J.  A.  Kesh 

I'.dgewood,  N.  Y. 

Paul  Mason 

Chester,  Penn. 

1       (  lerar,  .Adams  i!v:  Co 

Chicago,  111. 

^        Para  Rubhei  .Shoe  Company 

.     .So.  Kraminghani,  Mass. 

1        French  &  Ward 

Stoughton,  Mass. 

1        Irtnt'in  Iron  Company 

.    Trenton,  \.  J. 

1        Pennock  <.V  Haiternuirsier 

.     Chittenango,  N.  Y. 

1       Kclip.se  Mill 

North  Adams,  Mass. 

Atlantic  Cotton  Mill       .... 

.     Lawrence,  Mass. 

Yacht  "  N'amouna "        .         .        .        . 

New  N'ork. 

Pond  F'.ngineering  Company 
I       Little  Kails  Knitting  Company 

St.  Louie,  Mo. 
.     Little  Kails,  N.  Y. 

f       G.  Ci.  Young 

.     New  \'ork. 

1       The  New  York  Steam  Company  . 

New  York. 

'        L.  L.  Smith 

C.  A.  Seley 

Ansonia,  Conn. 
St.  Paul,  Minn. 

James  L.  Howard  &  Co. 

Hartford,  Conn. 

J.  \i.  Sargent 

Hurlington  Manufacturing  Company    . 
IJrayton  Petroleum  Knginc  Company  , 
N.  F.  Palmer,  jun.,  &  Co. 
Swamscot  Machine  Company 

A.  R.  Yale 

Hamilton  Woolen  Company 

James  Poyd 

lummer  Kngine  Company    . 
Amoskeag  Manufacturing  Company     . 

H.  W.  Kelsey 

lirown  &  Sharpe  Manufacturing  Co.    . 
I).  H.  Cruickshank         .... 

Thomas  Evans 

John  C.  Palmer      ..... 
Charles  P.  Harris  Manufacturing  Co.  . 

W.  H.  Hone  

E.  M.  Strang 

A.  B.  Farquhar       ..... 

Robbins,  Ciamewell  &  Co.     . 

Stark  Mills 

Lancaster,  Mass. 

Burlington,  Vt. 

E.  Bridgewater,  Mass. 

New  York. 
.     So.  New  Market,  N.  H. 

Meriden,  Conn. 

Amesbury,  Mass. 

Philadelphia,  Penn. 
.     Detroit,  Mich. 

Manchester,  X.  H. 

Nashua,  N.  H. 

Providence,  R.  I. 

Providence,  R.  I. 

Providence,  R.  I. 

Hamilton,  O. 

Rutland,  Vt. 

Cleveland,  (>. 

Baltimore,  Md. 

York,  Penn. 

Pittsfield,  Mass. 

Manchester,  N.  H. 

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^^*j>«j^^ 

^¥^          Pmr'iQaq  St^am  Qau^^  ^o.,  BostoQ. 

% 

Kagic  lr(in  WuiKh 

.    F.au  Claire.  Wis. 

A.  (;.  I'hillips 

Hutte  City,  Mon. 

().  II.  I'trry 

Lowell,  Mass. 

Thoma.".  II.  (  onncll        .... 

Lowell,  Ma.Hs. 

T.  W.  lIuKo 

Duluth,  Minn. 

t  (ilumlii.nn  M.iiuifarturing  Company    . 

Greenville,  N.  H. 

Charles  A.  Kichard.s      .... 

Hridgeport,  Conn. 

liarnal))'  Manufacturing  C^onipany 

Fall  Rivei,  Mass. 

P.  n.  .Skiflniore  &  .Son  .... 

Ilridgeport,  Conn. 

1 

Watts,  <.'anii)bcll  iV  Co. 

Newark,  N,  J. 

Oeorge  W.  Wiliiani.s  &  Son  . 

Charleston,  S.  C. 

Sterling  Organ  Company 

Itirmingham,  Conn. 

1 

J.  K.  Clark 

Putte  City,  Mon. 

Canadian  Locomotive  and  Kngine  Compan_ 

S 

Kingston,  Ont. 

Kohert  Ixodnian 

.     La  layette,  R.  L 

R.  11.  Thurston 

Iloboken,  N.J. 

H.  S.  Nichols  &  Co 

Purlington,  Vt. 

James  A.  I'latt 

Chester,  Pcnn. 

J.  F.  Ridge  way 

.St.  Louis,  Mo. 

I*.  &  F.  Corbin 

New  Hritain,  Conn. 

N.  O.  Nelson  Manufacturing  Company 

St.  Louis,  Mo. 

C.  II.  North  &  Co 

F.  Cambridge,  Mass. 

E.  (;.  Studley  &  Co 

(irand  Rapids,  Mich. 

Walsh,  I)c  Koo  &  Co 

Holland,  Mich. 

David  Jenkins 

Sheboygan,  Mich. 

E.  H.  Gowing 

Reading,  Mass. 

Bowman  &  Kellogg        .... 

Atchison,  Kan. 

Green  &  Daniels  Manufacturing  Comp.'>ny 

Pawtucket,  R.  L 

Joyce,  Cridland  &  Co 

.    D.iyton,  0. 

S/i(iiig/iai  C.  C.  Mill  Company 

S/i(ini^liiii,  China. 

James  Sheriffs 

Milwaukee,  Wis. 

The  Bozrahville  Company     . 

Pozrahvilhi,  Conn. 

China  Manufacturing  Company    . 

Suncook,  N.  H. 

Schaffcr  &  Hudenberg  .... 

Nev  \'ork. 

Joliet  Steel  Company    .... 

Joliet,  III. 

(ieorge  II.  Gilbert  Manufacturing  Company 

.     Ware,  Mass. 

Webster,  Camp  &  Lane  Machine  Company 

Akron,  O. 

Southwalk  Foundry  and  Machine  Company 

Philadelphia,  Penn. 

Anaconda  Gold  and  Silver  Mining  Company 

lUitte  City,  Mon. 

Melrose  Milling  Company 

Evans ville,  Ind. 

Rockdale  Mill 

Northbridge,  Me. 

Hope  Company 

Hope,  R.  L 

Rhode  Island  Electric  Light  Company 

Providence,  R.  L 

R.  M.  Lodge 

.     Philadelphia,  Penn. 

F.  H.  Mayes 

Holyoke,  Mass. 

Pacific  Mill 

Lawrence,  Mass. 

I.  R.  Scott 

Utica.  N.  V. 

Rhode  Island  Locomotive  Works 

Providence,  R.  L 

Struther,  Wells  &  Co 

.     Warren,  Penn. 

^ 

^ 

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'Mf 


pm^ri(,39   Steam   Q3U^(i   ^       Bosto 


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m 


}..  V.  Osborne     :    .        •        .        ,        .. 
Ncafi«'  iV  levy         ..... 
.Newmarket  Manufacturing  (umpiiny   . 

Jarvis  Itarnet  &  Cd 

1'..  r.  Watson  &  .Son      .... 

A.  M,  I»avy 

(irosvcnor  Dale  Company     . 
(.■innnuT  lMtf{ine  Company     . 
Charles  I'!.  J.iuks     ..... 
kufiis  K.  Town.'^cnil       .... 
Iron  iiay  .Maniilai  tiiring  Company 
Saunders  '  'otton  Mill     .... 

Rets,  Shook  iV  Co 

ir.  I,   Nott 

J.  II.  He((.x 

II.  \\';irrington        ..... 
J.-ickson  Foundry  and  Machine  Company 

Monadnock  Mill 

Nordykc  and  Marmon  Company  . 
Michigamme  Company 
Wallace  &  Hrother         .... 
Morgan  Envelope  Company 
Corliss  Steam-Kngine  Company    . 

Frank  A.  Foster 

Daniel  Ashworth 

D.  W.  Mur|)hy 

L.  W.  Cumpung.s 

John  W.  Turner 

Fldwin  Stangcr 

E.  C.  Perry  &  Co 

J.  Snow  &  Co.         ..... 

Silver  Spring  Uleaching  and  Dyeing  Company 

Edward  Watson 

William  H.  Heinent  &  Son 

S.  C.  Forsaith  &  Co 

Fitchburg  Steam-Enginc  Company 
I'hcenix  Chair  I'onipany 

J.  K.  Foss 

S.  M.  Van  Clief,  M.  E 

W.  R.  Smith 

New  \ork  Safety  Steam-Power  Company 
Exposition  Cotton  Mill 

A.  J.  Van  Ness 

H.  R.  Worthington         .... 
Lewis  Johnson 

F.  Van  Winkle,  M.E 

E.  F.  Williamson 

Merchants'  Mill 

American  Triple  Thermo  Union  . 


.St.  Paul,  Minn. 
Phil.idelphi.t.  Pvon. 
Ntwm.ukei,  N.  H 
I.anHing,  Michigan. 
New  N'ork. 
Detroit,  Mich, 
(irosvcnor  Dale,  Conn. 
Cleveland.  ( ». 
Cential  Falls,  R.  I. 
Albany,  N.  V. 
Marquette,  Mich. 
Saunilersville,  Mass. 
Pittsburgh,  Penn. 
Norwich,  Conn. 
Westborough,  Mass. 
Chicago,   111. 
Jackson,  Mich, 
t'laremont,  N.  H. 
Indianapolis,  Ind. 
Michigamme,  Mich, 
lialtimore,  Md. 
Springfield,  Mass. 
Providence,  R.  I. 
New  Haven,  Conn. 
Cincinnati,  O. 
Heverly,  Mass. 
Waterbury,  Conn. 
Mazeppa,  Minn. 
Philadelphia,  Penn. 
Dunkirk,  N.  V. 
Tuscaloosa,  Fla. 
Providence,  R.  I. 
Newark,  N.  J. 
Philadelphia,  Penn. 
Manchester,  N.  H. 
Fitchburg,  Mass. 
Sheboygan,  Wis. 
Reading,  .Mass. 
New  Vork. 
Oswosso,  Mich. 
New  Vork. 
Atlanta,  Ga. 
New  Vork. 
New  \'ork. 
New  Orleans,  La. 
New  Vork. 
Philadelphia,  I'enn. 
Dedham,  Mass. 
New  \'ork. 


_**S_. 


.3 1 


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r 


f\(r\er'\Qat)  Steam  C^o^e  ^o.,  BostoQ. 


If' 


J.  K.  UoKcrH  \  Co. 

Mo!)tni>iniry  lie  Maiuifatturinn  <  ()ni|tai>y 

I'idiHoti  I'^lfciric  llliiniinator  rompany  • 

'rhoiiu's  Mannii)g,  jiii).  . 

\V.  A.  I  lowland     . 

W    (',.  Cuyli-  \  Co. 

Wliiiiu-y  Iron  Wfirks 

Doiaii  \  SiiiitI) 

Laurel  lake  Miiln 

Dodne  Maiiufa<  luring  Company 

Novelty  Iron  Woi  ks 

I'hd-nix  Iron  Company 

William  Wriglit     . 

Williams  &  Orifii  Manufacturing  Company 

I.  K.  Swift      .... 
Irwin  iV  Ikissncr    . 
lusmnaycr  Company     . 
A.  L,  Archambault 
K.  M.  lUirna,  Kerconi 
(Jcldon  llrotliers     . 
John  N.  Paul 
AllenIiLiiy  City  Water  Works 

II.  Kirmistccr 

Goodytar  Metallic  Ruhher  Shoe  Company 
C.  r.  Williamson    . 
Richmond  I'ajjcr  Company   . 
W.  n.  Clohum,  juii. 
Milwaukee  Machine  Company 
G.  II.  Morrison 
National  Tube  Works  . 
Colt's  Patent  Fire-arms  Manufacturing  Compan 
Strong  Locomotive  Kngineering  Company 
E.  V.  Davis    .... 
John  C.  Froehlich  &  Co. 
S.  E.  Cobb      .... 
Lynn  Iron  Company 
A.  D.  Traverr. 
Frank  Mitchell 
J.  Mendy  Machine  Works     . 
Swain,  Earle  &  Co. 
Cooke  &  Co.  .... 
Anton  IJorges 
Hraman,  Dow  &  Co. 
Charles  E.  Rice 
Oshkosh  Water  Works 
Abiles,  Cook  &  Co. 
Kensington  Engine  Woiks    . 
Hancock  Inspirator  Company 
Warren  A.  Carr 


riiiludt'lphia,  I'cnn 
Montnontcry,  .Ma. 
Hrockinn,  Masts. 
I  leviland.  < ». 
Lowell,  \\,i*%. 
\i'\v  <  >rliMii-<,  La. 
New  <  Irlfaii!*,  La. 
Lc  Sueur,  Minn, 
r.dl  River,  .Mass. 
\\  ii.tiiaka,  Ind. 
New  Orlians,  La. 
Trenton,  N.  J. 
N>.w!>iirn,  N.  \'. 
Sterling,  111. 
Ishpemiii;^,  Mich. 
Galveston,  Tex. 
Little  R'uk,  Ark. 
Philadelphia,  Penn. 
Northfield,  Mass, 
<  'olumbus,  (ia. 
Middlctown,  (). 
.Mlenlicny,  Penn. 
Lon^d-de,  V'a. 
Nauyatuck,  Conn. 
Itiriningham,  Ala. 
Providence,  R.  I. 
Utica,  N.  Y. 
Milwaukee,  Wis. 
Pacific,  S.  C. 
McKeesport,  Penn. 
llartfonl,  Conn. 
Philadelphia,  Penn. 
Pottsville,  Penn. 
Haltimore,  Md. 
Terre  Haute,  Ind. 
Birmingham,  Ala. 
Cleveland,  O. 
E.  Killiiigly,  Conn. 
San  Francisco,  Cal. 
Hoston,  Mass. 
New  \'ork. 
New  York. 
Worcester. 
Lockland,  O. 
Oshkosh,  Wis. 
Little  Rock,  Ark. 
Philadeli)hia,  Penn. 
Montreal,  Can. 
Brockton,  Mass. 


u 


3« 


1W)8.  FBAY,  JB.,  CoMWltlai  SiiitaMer, 

95  MILK  BTRKET  (Room  71),  BOSTON. 


Boston,  Mais.,  Oct.  84,  1890. 
BBtOAH  BtBAM  Gauob  Co.,  Botiton,  Mom.  : 

^d^m^lfff^y  J-  Your  inquiry  of  Oct.  23,  asking  m«  "  to  give  you  my 
till  l^icpV  the  merits  and  demerits  of  the  Thompson  improved 
satbr,  as  mana&ctured  by  your  company,"  is  the  first  tame  in  a 
^fassionilf  career  of  mofe  than  twenty  years  that  any  corporation 
ir  aslied  me  to  tell  them  the  outs  of  their  instruments. 
[  Yon  also  malce  a  second  inquiry  **  with  reference  to  what  was  my 
Iperfence  with  the  Thompson  indicators  on  the  second  official  trial  of 
)  United  States  steam  cruiser  "Baltimore,"  built  by  the  William 
imp  &  Sons*  ShiD  and  Engine  Building  Company  for  the  United 
ktet  government.  Navy  Department." 
rTo  the  second  inquiry  I  can  only  answer  in  a  general  way,    I  was 
[iployed  by  the  Wiltiafn  Cramp  &  Sons*  Ship  and  Engine  Building 
mipany  to inveHttgHte %Ke  reason  why  the  cruiser  ** Baltimore"  only 
ftde  8,977.2  horee-pfj^/er  on  her  first  official  trial,  and  to  suggest  any 
iprovements  which  could  be  made,  etc.    After  a  careful  examination 
'  the  diagrams  in  the  judge  advocate's  office  of  the  Navy  Depart- 
pent  of  the  United  States,  at  Washington,  and  some  ten  days  spent 
ver  the  drawings,  models,  etc.,  in  Cramp  &  Sftns'  ship-yard,  and  on 
he  ship  examining  the  engines,  I  suggested  certain  changes  which 
liould  be  made  and  which  were  afterward  made  by  consent  of  Engineer- 
a-Chief  Melville,  of  which  alterations  I  had  personal  charge  for  Cvamp 
b  Sons,  by  consent  of  the  Navy  Department.    All  of  these  ^changes 
rere  inspected  by  the  officers  of  the  United  States  government  then  on 
luty  at  Cramp  &  Sons'  ship-yard. 

When  the  alterations  were  finished,  I  was  sent  to  the  New  York 
favy  Yard,  where  I  acted  jointly  with  certain  officers  of  the  United 
States  Navy  Department,  detailed  by  Engineer-in-Chief  Melville,  and 
»ndeT  the  immediate  personal  supervision  of  Chief* Engineer  Dungan, 
'  the  New  York  Navy  Yard,  and  I  assisted  in  the  official  test  of  the 


Thompson  indicators  made  by  your  company  for  the  Navy  Departmentj 
for  the  cruisers  "Baltimore"  and  "Philadelphia,"  preparatory  to  tlij 
instruments  being  sent  to  the  ship  to  take  the  diagrams  which  wouh 
form  the  basis  of  setllement  between  the  Navy  Department  and  Orainpl 
&  Sons,  which  was  on  the  basis  of  $100  for  every  indicated  horse- 
power  made  by  the  ship  above  9,000,  during  the  official  trial  run  of  foiirl 
consecutive  hours.    This  statement  is  necessary  in  order  to  convey  an! 
idea  of  the  importance  attached  to  that  trial,  as  well  as  the  test  which 
preceded  it,  and  also  to  enable  me  to  answer  your  first  question,  from 
the  circumstances  which  can  only  be  brought  out  by  answering  the| 
second  question  first  in  order. 

The  builders  of  the  ship  were  under  a  guarantee  to  furnish  9,000 1 
indicated  horse^power,  in  which  they  failed  on  the  first  official  trial,  hv 
a  fraction  less  than  23  indicated  horse-power.  * 

The  engines  were  supposed  to  be  capable  of  more  than  10,000  indi- 
cated horse-power.  It  is  unnecessary  to  say  here  what  alterations! 
were  made,  or  why  ;  but  after  the  alterations  were  made  in  the  engine.s, 
as  is  stated  earlier  in  this  letter,  we  commenced  the  test  of  each  instru- 
ment and  spring  with  the  mercury  column  and  steam  gauge,  these 
being  the  ''standards  used"  in  the  United  States  Navy  Yjird  at  New- 
York,  neither  of  which  instruments  were  made  by  your  company. 
Tery  early  in  the  test  I  filed  an  objection,  which  Chief  Engineer  Dun- 
gan,  on  careful  examination,  immediately  allowed,  and  the  instruments 
were  then  tested  by  a  standard  test  gauge  made  by  your  company, 
corrected  for  the  mercury  column  (in  which  we  found  eiTors).  Then 
the  coiTections  of  the  corrected  mercury  column  were  worked  out  for 
the  steam  gauge,  and  found  to  be  slight,  and  all  the  indicator  springs 
were  tested  at  five  and  ten  pound  intervals,  according  to  the  require- 
ments of  the  Bureau  of  Steam  Engineering  of  the  Navy  Department, 
and  upon  this  basis.,  after  the  official  trial,  all  the  corrections  were 
made  in  computing  the  horse-power  of  the  ship. 

When  we  came  to  test  the  low-pressure  cylinder  springs,  I  filed  a 
written  objection  to  the  standard  instrument  furnished  by  its  builders 
to  the  Navy  Department,  called  a  vacuum  test  gauge. 

This  objection  of  mine  called  forth  a  very  spicy  letter  from  the 
Bureau,  which  was  received  only  an  hour  before  I  left  the  Navy  Yard 
with  the  instruments  and  the  officers  in  whose  custody  they  were  to  be 
sent  on  board  the '*  Baltimore." 

We  went  to  sea  Nov.  13,  anchoring  that  night  neai*  the  I>eiaware 


;akwater.     The  aext  day  we  went  to  the  open  sea  with  the  ship  for 

tr  own  test,  and  I  ran  the  engines  of  the  '*  Baltimore  '*  with  126^ 

^unds  of  steam  at  118.6  revolutions  for  over  two  hours,  during  which 

le  Chief  Engineer  8.  L.  P.  Ayres,  in  charge  of  the  engineering 

rps,  very  courteously  acceded  to  my  request  to  have  the  assistants 

^t  the  indicators  on  the  engines  of  the  "  Baltimore  "  and  take  some 

rds,  that  I  might  get  at  the  action  of  the  valves  and  make  any  further 

mges  which  were  necessary  for  the  official  trial  that  was  to  occur  the 

llowing  day.     The  action  of  the  instruments  on  Thursday,  to  which 

Iference  was  made  immediately  above,  was  ererything  that  could  be 

isired.     After  the  United  States  officers  had  taken  cards,  which  were 

indcd  over  to  me  for  computation,  the  instruments  were  returned,  each 

le  to  the  custody  of  the  man  who  was  to  manipulate  it  on  the  morrow, 

id  the  ship  was  headed  back  for  her  anchorage  inside  the  breakwater. 

On  Fi'iday,  the  15th  of  November,  we  left  the  breakwater  about  six 

2loek  A.  M.,  and  went  directly  out  to  sea  and  van  the  ship  from  7.25 

7.55  under  a  full  head  of  steam,  when  Chief  Engineer  Ayres  cpj^.. 

jienced  the  official  test  of  four  hours. 

At  twelve  o'clock  h.,  after  running  four  hours  and  five  minutes,  offi- 

|al,  not  a  single  accident  had  occurred  to  any  one  of  the  indicators  from 

ly  fault  of  the  indicator.     Not  a  singe  card  was  omitted,  nor  was  a  sin- 

le  card  soiled  or  lost,  twelve  indicators  being  used  on  both  engines  and 

)ur  on  the  auxiliary  machinery,  diagrams  being  taken  at  intervals  of 

teen  minutes ;  the  whole  192  cards  of  main  engines  being  formally 

tumbered  and  filed,  not  a  single  one  of  which  contained  a  single  inac- 

luracy  which  prevented  its  being  computed.     During  that  time  two 

the  indicators  were  seriously  injured  in  the  pencil  bar,  only  by  the 

irelessness  of  a  man  in  passing  up  or  down  the  ladders  between  the 

i|ratings  in  catching  the  leg  of  his  pants  in  the  pencil  motion.     These 

rere  immediately  replaced  by  others  (Thompson's)  to  complete  the 

[fficial  record.     Aside  from  this,  no  mishap  occurred  to  any  one  of  the 

Instruments.     The  high-pressure  cylinder,  carrying  123  to  125  pounds 

»f  steam  on  the  diagram,  engines  running  at  about  118  revolutions  per 

linute,  the  auxiliary  running  from  700  revolutions  per  minute  to  as 

[ow  as  32  strokes  on  the  punii>s,  some  of  the  places  being  difficult  of 

Recess,  and  others  being  where  a  man  had  to  step  over  the  indicator 

svery  time  an  observation  was  made. 

Now  and  then  a  cord  broke,  and  in  one  or  two  cases  men  lost  a 

jrew,  but  these  were  replaced,  as  I  had  provided  myself  with  them. 


The  result,  therefore^  of  the  test  of  the  ThompBon  indicators  is 
fiiuItlesH,  BO  far  as  operation,  adjustment,  and  accuracy  are  concerned. 
The  derangements  which  occurred  were  not  the  fault  of  the  instru- 
ments, their  design  or  construction,  and  no  trial  of  any  naval  vessel, 
either  American  or  foreign,  that  I  have  ever  attended,  went  off  in  so 
completely  and  thoroughly  successful  a  manner  as  did  that  of  the 
"  Baltimore,"  so  far  as  indicators  were  concerned,  on  her  second  official 
trial. 

In  the  previous  official  trial,  which  took  place  in  September,  1889, 
Thompson  indicators  were  only  used  to  replace  two  instruments  of 
anoUier  make,  used  on  the  liigh-pressure  cylinder,  where  a  part  of  the 
cap  blew  off,  crippling  the  instruments,  and  these  two  crippled  indica- 
tors were  replaced  by  two  Thompson  indicators  which  were  on  the 
ship,  and  they  performed  the  rest  of  the  duty  in  a  perfectly  satisfac- 
tory manner.  The  Thompson  instruments  were  employed  on  the 
Bratherhood  engines,  making  700  revolutions  per  minute,  which  were 
used  in  the  fire-rooms :  they  were  used  on  the  pumps,  making  32 
strokes,  on  the  auxiliary  condenser,  on  the  electric-light  engine, 
running  at  375,  answering  perfectly  in  every  place  the  requirements  of 
the  occasion. 

This  is  perhaps  sufficiently  explicit  to  answer  your  second  question. 
Now  as  to  your  first  inquiry,  I  have  yet  to  come  in  contact  with  the 
first  steam  gauge  or  indicator  in  the  United  States  to-day  that  is  abso- 
lutely correct,  and  this  refers  not  only  to  the  instruments  made  by 
your  company,  but  to  those  made  by  other  companies  as  well.  My 
personal  experience  in  this  matter  is  undoubtedly  as  good  as  that  of 
any  man  living. 

Fourteen  years  ago  the  standards  of  a  foreign  government  were 
corrected  absolutely,  and  the  objections  which  I  filed  with  the  Navy 
Department  while  in  the  employ  of  Wra.  Cramp  &  Sons,  on  the 
United  States  cruiser  "Baltimore,"  from  the  New  York  Navy  Yard, 
abdut  Nov.  26,  1889,  have  resulted  in  Engineer-in-Chief  Melville, 
United  States  Navy,  detailing  a  man  who  was  thoroughly  capable  to 
visit  the  New  York  Navy  Yard  in  January  or  February,  1890,  to  exam- 
ine into  my  objections  to  the  supposed  standards  then  in  use,  and  the 
final  result  has  been  that  the  scale  of  the  mercury  column  was  found 
incorrect  in  itself,  and  that  no  part  of  the  supposed  standard  instru- 
ment which  was  in  use  at  the  time  my  objections  were  filed  with  Chief 
Engineer  Dungan  now  remain  in  existence,  excepting  the  steei  tabe 


5 


lining  the  mercury,  the  float,  the  wheel,  and  the  index  from  which 

mercury  soile  was  read.     The  vacuum  te«t  gftuge  has  been  entirely 

indoned.    A  new  vacuum  gauge,  of  which  I  furnished  the  drawings, 

))een  arranged,   with   some  slight  modifications.     The  mercury 

^umn  has  been  corrected  for  latitude,  height  above  the  sea  level,  and 

gravity  factor  which  must  enter  into  all  physical  calculations,  and 

la  steam-engine  indicator  spring  and  a  mercury  column  and  a  vacuum 

|umn  are  all  within  the  realm  of  physics,  it  is  safe  to  say  that  unless 

Stevens  Institute  and  the  New  York  Navy  Yard   have  a  near 

>roximation  to  a  correct  mercury  column,  there  does  not  exist  in  the 

lited  States  to-day,  Oct.  24,  1890,  a  mercury  column  or  a  vacuum 

ige  that  is  correct.     It  must  follow  that  the  standards  not  being 

solute,  the  results  of  graduating  -  .y  instrument  whatever  from  these 

indards  must  necessarily  he  as  incorrect  as  the  standards  (f). 

|Men  who  make  instruments  for  sale  usually  consider  that,  if  their 

itruments  are  as  good  as  others,  they  are  all  right. 

[This  does  not  answer  your  question  fully,  in  my  way  of  putting  it. 

your  instruments  are  incorrect,  they  are  wrong,  and  that  is  exactly 

\y  basis.     Indicator  springs  give  to-day,  as  a  rule,  from  seven  to  as 

;h'as  thirteen  per  cent  more  power  on  an  engine  than  they  would 

re  if  the  springs  were  correct.     The  indicated  horse-power  of  the 

lited  States  cruiser  "'Baltimore"  by  the  instruments  which  had  been 

sted,  while  the  engines  were  running  on  Thursday,  Nov.  14,  com- 

ited  10»821  horse-power  without  correction.     The  official  computation 

the  power  for  the  four  hours'  run  was  10,119.68  horse-power.    This 

ikes  a  difference  of  701.32  horse-power,  which  was  deducted  from 

^e  reading  of  the  indicator  diagrams  in  order  to  make  the  correct 

lount  of  power  exerted  on  the  combined  main  and  auxiliary  engines 

that  ship  for  that  day.     Had  the  indicator  diagrams  been  absolutely 

)rrect,  it  would  have  added  over  $70,000  to  the  sum  paid  by  the 

[avy  Department  to  Wm.  Cramp  &  Sons,  which  was  $119,000,  as 

»tween  the  guaranteed  and  the  actual  result  of  the  second  official 

rial,  Nov.  15,  1889. 

It  remains  for  you,  therefore,  as  the  oldest  steam-gauge  company  in 

lis  country,  if  I  am  correct,  to  put  yourselves  in  a  position  to  make 

bsolute  instruments  for  commercial  use,  which  can  only  be  done  by 

)ing  t6  the  very  foundation  with  a  man  who  is  capable  of  working  out 

le  results,  and  you  can  have  as  nearly  absolute  instruments  as  any 

irvatcHry  io  the  world. 


**^ 


^e^' 


This  questiou  has  never  yet  been  considered  in  any  industrial  cor 
corn  in  the  United  States,  except  in  an  approximate  way.    It  h  a 
qaestion  of  several  thousands  of  dollars  to  do  this  properly,  and  tlienl 
it  may  be  a  question  of  expense  after  that  to  arrange  your  springs,  thej 
friction  of  the  instrument,  and  various  other  physical  questions,  which| 
can  only  be  done  from  a  careful  investigation  ;  but  I  hope  that  you  wil 
at  no  late  day  take  this  question  up  and  be  able  to  offer  A  correct  stesimj 
gauge,  a  correct  vacuum  gauge,  and  a  hydraulic  pressure  gauge.     In 
order  to  do  this,  the  exact  latitude  of  your  factory  must  be  ascertained, 
its  precise  height  above  the  level  of  the  sea,  and  then  the  absolute 
weight  of  a  pound  of  mercury  at  that  point,  under  a  certain  tempera- 
ture, and  the  gravity  factor  of  the  distance  from  the  centre  of  the  earth,! 
which  makes  a  differance  in  the  weight  of  a  pound  of  steel,  iron,  mer-| 
cury,  or  water,  must  also  be  included,  and  correctly. 

These  things  have  been  made  of  np  account,  and  my  proposition  to 
the  Navy  Department  was  at  first  ridiculed  as  far  as  courtesy  would 
allow  ;  and  Englneer-in-Chief  Melville  certainly  deserves  a  great  deal  of 
credit  for  carefully  looking  into  the  matter  afterward  and  availing  him- 
self, for  the  first  time  in  the  history  of  the  Navy  Department  of  the 
United  States,  of  all  these  quantities,  and  correcting  the  scales  for  lati- 
tude, gravity,  and  temperature.  The  lack  of  what  Mr.  Melville  has 
done  has  been  sharply  criticised  by  the  engineering  profession  the 
world  over,  and  personally  I  congratulate  myself  as  ah  American  that 
it  has  finally  been  thoroughly  done. 

It  is  only  a  question  of  time  when  every  concern  that  pretends  to 
manufacture  an  indicator,  steam  gauge,  vacuum  gauge,  mercury  col- 
umn, or  any  other  instrument  by  which  pressure  or  vacuum  is  to  be 
measured,  must  calculate  the  instrument  for  the  precise  spot  on  th  .> 
earth  where  it  is  to  be  located  and  used.  A  steam  gauge  made  .in 
Boston,  with  latitude,  gravity,  and  temperature  corrections,  may  be 
carried  to  any  latitude  or  longitude  in  the  world,  and  will  correctly 
record  the  problems  offered  to  it  or  observed  from  it.  A  pound  of 
mercury  is  different  in  Philadelphia,  New  York,  Boston,  Portland,  or 
London,  Paris,  or  Naples. 

It  remains  to  be  seen  now  whether  your  concern  has  the  enterprise 
to  lead  off  in  this,  or  whether  some  competitor  will  do  it.  The  day 
has  evidently  pa^jed  for  selling  instruments  which  have  no  foundation 
in  fact,  when  submitted  to  physical  observation  and  correction.  Some 
ot  our  clock  makers  have  found  (his  out  by  expensive  experience.  • 


lis  will,  fMrhaps,  answer  your  questions,  using  more  space  tiian 

anticipated ;  but  to  answer  them  fully  and  go  into  details  would 

)rfere  very  seriously  with  throe  books  which  will  shortly  be  brought 

by  my  publishers,  to  which  you  and  the  general  public  will  be 

jTerred  for  full  particulars. 

Personally  and  professionally  I  have  been  accused  of  too  much  fovor- 

»m  for  the  Thompson  indicator.     My  reasons  for  such  preferences 

as  follows :  — 

[It  is  over  twenty-five  years  since  your  comi)aoy  made  the  first  pair 

Richards  indicators,  which  I  used.     It  has  been  my  privilege  to 

every  instrument  ever  made  that  had  any  reliability.     Years  ago  I 

[id,  what  I  can  to-dny  say  stronger  than  ever,  that  when  I  am  on  a 

aamship,  a  locomotive,  or  any  other  of  the  larger  engines  on  which  I 

illy  work  now,  I  use  the  Thompson  indicator  for  the  adjustment  of 

^Ives  exclusively,  from  the  fact  that  its  delicate  record  of  the  chang- 

^g  of  position  of  the  valves  is  not  equalled  by  any  other  instrument 

it  I  have  ever  yet  seen  or  used. 

I  use  any  indicator  for  general  work  which  the  parties  have  or  desire 
use.     I  have  tested  the  springs  of  all  indicators,  and  am  now  on  a 
imittee  to  further  these  tests,  which  has  already  lieen  nearly  one  < 
sar  in  existence. 

I  have  to-day  the  largest  engines  in  the  world' to  look  after,  and  on 
sveral  steamers,  which  for  the  last  five  years  I  have  had  charge  of, 
ive  invariably  used  the  Thompson  idiproved  indicator  made  by  your 
>mpany. 

I  have  only  wished  that  they  were  absolute,  or  within  an  exceedingly 
[mall  limit  of  absolute,  as  it  would  save  a  vast  amount  of  time  in  com- 
>utation,  and  there  is  no  reason  why  the  instrument  cannot  be  made 
practically  absolute,  in  a  commercial  way,  with  ordinary  care. 

The  fact  that  five  hundred  indicators  are  used  now  where  one  was 
ised  ten  years  ago  would  seem  to  be  a  sufficient  incentive  to  do  this 
rark.     All  of  which  is  respectfully  submitted. 

Yours  truly,       THOMAS  PRAY,  Jb. 


Note.  —  Ag  to  the  capacity  of  the  Thompoon  indicators,  I  can  only  say  that  I  have  used  the 

liompeon  No.  1  on  four  hundred  and  thirty-five  revolutions  per  minute  (see  "Twenty  Years 

rith  the  Indicator,"  pages  162, 163),  and  the  Thompson  improved  No.  2  on  six  hundred  acd 

forty-two  revolutions  by  the  register  (see  "Twenty  Years,"  pages  217-224).    Since  that  time 

the  No.  2  instrument  has  done  work  at  Heven  hundred  and  twenty  revolutions  per  minute,  by 

ctnai  mechanical  counting. 


»,  ' 


m 


f|*^           f\n\emaT)  Steam   (Jau^e  $o.,  BostOQ. 

n 

TW 

H.  T.  Haitlctt 

A.  \V.  Stahl    .... 

Grirtin  Manufatiiiiing  Coiiipaiiv 

Charles  A.  Hague 

\ovflty  Machine  Works 

.     New  NOrk. 
.     fa  Fayette,  Ind. 
.     <  Irittin,  Ga. 
.     Chicago,  III. 
.     Kv.insvillc,  Inil. 

I'ulltnan  I'alaccCar  (.'ompany 

(  liicagt),  111. 

M.  V.  I'ennyvvcll     . 

Hamilton,  O. 

W.  H.  jaiULson 

Wilson,  Kan. 

Hurnhani  Hanson  . 

I'ovcr,  N.  II. 

James  Krietf  .... 
Boston  Woven  Ilc^e  ('ompany 

.Magnoville,  Cal. 
Boston. 

Hcrtram  lirotlicrs  . 

New  \'ork. 

O.  Matheson  &  (  o. 
Crook,  Horner  &  Co. 

.     New  Glasgow,  S.  C. 
iiahimorc,  Md. 

John  M.  Leach 

John  Post,  jmi.,  &  Co.    . 

.     Kvansvillc,  Ind, 
Boston,  Mass. 

H.  C.  Burke   .... 

.     St.  Paul,  Minn. 

P.  A.  Noble    .... 
John  Kxton    .        -        .        . 

.     .S])ringfield,  Mass. 
Trenton,  N.  J. 

F.  Grote  &  Co. 

New  York. 

E.  O.  Kelsey  .... 
Whitten  Cotton  Mill      . 

Lowell,  Mass. 
.     Providence,  R.  I. 

Carnegie,  Phip])s  &  Co. 
Paterson  Association  Stationary 
Canadian  Pacific  Railway 
G.  A.  Know   .... 
Fred  Wolff     .... 
Remington  &  Henthorn 

Engl! 

le 

.     Pittsburgh,  Penn. 
Paterson,  N    J. 
Montreal,  Can. 
Boston   A'ass. 
Chicago,  ill. 
Providence,  R.  I. 

Allen  Print  Works 

Providence,  R.  I. 

James  Lockart       .... 
Baltimore  &  Ohio  K.R.  Co.  . 

Philadelphia,  Penn. 
Baltimore,  Md. 

Frank  L.  Cottrell  . 

E.  T.  Dixon    .... 

Union  City,  Fa. 
Millbank,  S.  D. 

Geo.  Hornung 
Andrew  Ringwald  . 
Thomas  M.  Wilson 
J.  A.  Crouthers 

Cincinnati,  O. 
Fly  Mountain,  N.  V. 
Independ«;nce,  Mo. 
New  York,  N.  Y. 

V 

1 

Jas.  Milne       .... 

Montreal. 

s 

The  W.  Bingham  Co.    . 

Cleveland,  O. 

'■ 

Reid  &  Creighton  . 

Fred.  Phelps  .... 

Milwaukee,  Lake  Shore  &  Wester 

n  Ry 

.  Co. 

Fall  River,  Mass. 
Newark,  N.  J. 
Milwaukee,  Wis. 

E.  L  Noxon    .... 

Jamestown,  Dak. 

C.  H.  McCutcheon 

Buffalo,  N.  Y. 

Strong  &  Tiowbridge     . 

A.  (j.  Turner          .... 

New  York,  N.Y. 
Willimantic,  Ct. 

Jas.  W.  Birkett      .... 

Brooklyn,  N.Y. 

Blue  Ridge  Marble  Co. 

Nelson,  Ga. 

Walter  Barnsdale  . 

Los  Angeles,  Cal. 

i 

0 


'fm 


^p~        /»m?ri8ai)  S»ean>  <ja<"5«  5°-  Bostop.  ^ 


Iowa  Iron  Works  Co.    . 

John  Rourke  . 

Eclipse  Wind  Kngine  &  Tump  Co 

Rockwell  Machine  &  Car  Co. 

J.  W.  Holmes 

A.  J.  Wilkinson  &  Co.  . 

American  Steam  Hoiler  Insurance 

Milwaukee  (!emcnt  Co. 

Robert  Harnsdalc  . 

I,.  C.  Haumgarten  . 

Hydraulic  Milling  Co.    . 

Foster's  Wharf  Co. 

The  J.  Morton  Poole  Co. 

Rus.sell,  Boynton  &  Co. 

The  Hooven,  Ownes  &  Rentschl 

The  Geo.  Worthington  Co.  . 

Willamette  Steam  Mill 

Calumet  &  Hecla  Mining  Co. 

John  Mathie  .... 

Dallas  Cotton  &  Woolen  Mills 

Robinson  &  Cary  Co.    . 

Star  Brass  Mfg.  Co. 

Warner  &  Co. 

The  Engineers'  Co. 

National  Transit  Co.     . 

Cleveland  Supply  Co.    . 

Wilmington  Water  Works    . 

Skenandoa  Cotton  Co.  . 

The  Weisel  &  Vilter  Mfg.  Co. 

Holyoke  Machine  Co.    . 

Russell  &  Co. 

Christ.  Dannheiser 

Elmira  Water  Works    . 

Charleston  Water  Works 

Temple  St.  Cable  Railway  Co. 

Bowker  &  Tripp     . 

U.  S.  Wind  Engine  &  Pump  Co. 

Towle  Mfg.  Co.      . 

Sherman  Oil  &  Cotton  Co.    . 

Horace  C.  Thomas 

Dallas  Water  Works     . 

Chicago  Steel  Works    . 

J.  T.  Elliott    .... 

Falls  City  Jeans  &  Woolens  Co. 

Morss  &  Whyte 

E.  W.  Thurston     . 

The  Journal  Co..    . 

Jos.  B.  Smith 

Mcintosh,  Huntington  &  Co. 


er  Ci 


Co. 


Dubuque,  la. 
Savannah,  Ga. 
lleloit,  Wis. 
Sandusky,  O. 
I'aducah,  Ky. 
Boston. 

New  York,  N.V. 
Milwaukee,  Wis. 
Coronado  Beach,  Cal. 
Hornellsvillc,  N.V. 
Wichita,  Kan. 
Boston. 

Wilmington,  Del. 
Minneapolis,  Minn. 
Hamilton,  O. 
Cleveland,  O. 
Portland,  Ore. 
Calumet,  Mich. 
Knoxville,  Tenn. 
Dallas,  Tex. 
St.  Paul,  Minn 
Boston. 

New  Orleans,  La. 
Chicago,  111. 
Oil  City,  Pa. 
Cleveland,  O. 
Wilmington,  Del. 
Utica,  N.Y. 
Milwaukee,  Wis. 
Worcester,  Mass. 
Massillon,  O. 
Mt.  Veinon,  O. 
Elmira,  N.V. 
Charleston,  S.C. 
Los  Angeles,  Cal. 
New  Bedford,  Mass. 
Batavia,  111. 
Newburyport,  Mass. 
Sherman,  Tex. 
Petersburg,  Ind. 
Dallas,  Tex. 
Chicago,  111. 
Duluth,  Minn. 
Louisville,  Ky. 
Boston. 
Neenah,  Wis. 
Kansas  City,  Mo. 
Chester,  Pa. 
Cleveland,  O. 


34 


f\in<irKarj  Steam  (jauf^  $o.,  Bostoi;. 


^ 


Fox  Machine  Co Grand  Rapids.  Mich. 

Ira  Winsor  &  (-'o rrovidcnce,  Rl. 

West  I'oint  Foundry  Co West  I'oint,  (la. 

Providence  .Steam  Engine  Cc Providence,  Rl. 

Chas.  Recder  &  Sons Ilaltimore,  Md. 

Chas.  H.  Howers Chester,  Pa. 

Buffalo  Steam  Pump  Co Huffalo,  N.V. 

Ashland  Iron  Mining  Co Ironwood,  Mich. 

Knoxville  Foundry  &  Machine  Co Knoxville,  Tenn. 

Plymouth  Cordage  Co Plymouth,  M;iss. 

Concordia  Electric  Eight  Co Concordia,  Kan. 

The  Eaton,  Cole  &  Purnham  Co New  York,  N.Y. 

Pittsburgh  Traction  Co Pittsburgh,  Pa. 

Columbian  Iron  Works  &  Dry  Dock  Co.      .        .        .  Haltimore,  Md. 

Oliver  &  Imboden  Co Wichita,  Kan. 

P.  P.  Kellogg  &  Co Springfield,  Mass. 

Hutchinson  Water,  Light  &  Telephone  Co.  .        .  Hutchinson,  Kan. 

Mark  L.  Thomas Wheeling.  W.  Va. 

Mexican  Central  R.  R.  Co Poston. 

R.  M.  Spedden  &  Co Baltimore,  Md. 

Frank  Slater Fitchburg,  Mass. 

Fitchburg  Gas  Co Fitchburg,  Mass. 

The  I.  &  E.  Greenwald  Co Cincinnati,  O. 

Sherriff  Machinery  Co.  .        .        .  •        ■  Pittsburgh,  Pa. 

J.  S.  Paine Boston. 

Wm.  M.  Mathiesen Chicago,  111. 

Wilkin  Mfg  Co Milwaukee,  Wis. 

Brush  Elect      Light  &  Power  Co Memphis,  Tenn. 

Connecticut  River  Lumber  Co Mt.  Tom,  Mass. 

Liddell,  Hunter  &  Co Dallas,  Tex. 

Home  Electric  Light  &  Power  Co Shelbyville,  Ind. 

Brush  Electric  Light  Co Galveston,  Tex. 

School  of  Technology Atlanta,  Ga. 

John  A.  Peebles Yo.ko/iama,  Japan. 

Cooley&Vater Minneapolis,  Minn. 

Portland  Cordage  Co Portland,  Ore. 

Major  W.  R.  Livermore,  U.S.A Newport,  R.I. 

Wm.  J.  Silver S^'t  ^^^^'^  ^'^y'  ^''*^- 

Woonsocket  Spool  &  Bobbin  Co Woonsocket,  K.I. 

C.  J.  Reilly Denver,  Col. 

New  Orleans  Railway  &  Mill  Supply  Co.     .        •        •  New  Orleans,  La. 

Frontier  Iron  &  Brass  Works Detroit,  Mich. 

Lindsay  &  Robson Humboldt.  Kan. 

Stearns,  Roger  &  Co Denver,  Col. 

Rix  &  Firth ^*"  Francisco,  Cal. 

Porter  Mfg.  Co Syracuse,  N.Y. 

Globe  Iron  Works  Co Cleveland,  O. 

Fort  Worth  Electric  Light  Co Fort  Worth,  Tex. 

Robert  Wylie Cincmnat.,  O. 


35 


f\([\er\Q3r)  Steaff^  Caupe  C;o..  BostOQ. 


•  + 


Co, 


Schcntciady  Locomotive  Works 

I..  I'rcMott 

(lark  Siiitz 

Jacol)  I  (old  racking  (\). 

Frank  Jones    . 

K.  \  A.  II.  Hatchcl!er& 

University  of  Kansas 

(ieo.  Millbank 

I).  A.  Wise     . 

Irving  II.  Reynolds 

Hall  &  (  o.      . 

H.  P.  (Iregory  &  Co. 

K.  M.  Ooodall 

Mttle  Falls  Wool  Kxtract  Co. 

Henry  A.  Vesin 


36 


Schenectady,  N  N' 
Oniah.i,  Neb. 
Springfield,  ( ) 
Kansas  <  ity,  .Mo. 
I'ortbinoiilh,  .\.  H. 
Nu.  Urookfield,  Mass. 
Lawrence,  Kas. 
<"tiillicothe,  Mo. 
Topeka,  Kan. 
Milwaukee,  Wis. 
Jamestown,  N.V. 
San  Francisco,  Cal. 
Philadelphia,  I*a. 
Little  Falls,  N.V. 
Great  Falls,  Mont. 


B 


e> 
m 

Vi 


;^ 


/^m<?riGa9  Steam   Oaa^i?  Qo..  BostOQ. 


THE  STEAM-ENGINE   INDICATOR. 
BenefltH  Ihrlved  ami  Iv format hm  AHclahuil  frotn  Itn  I 


nr. 


The 


c  iiitormation  ascertaiiinl   from  the 
,  art'  vaiiid  and 


irnportaiu. 

We  (iiKiti-,  li\  permission  from 
"Hill's  Manual."  iJiihlislied  hy 
William  A.  Harris,  huildi-r  of  the 
Ilanis-Corliss  steam  eii<,Miic,  Pnjvi- 
dencc,  K.  I.  :  — 

"The  office  of  the  indicator  is,  to  furnish 
a  diagram  of  the  action  of  the  steam  in  the 

cylinder  of  an  fiinine  during;  one  or  more 
revdliitions  of  the  cranix,  from  whit  h  is  de- 
ducted the  following  data  :  Initial  pressure 
in  cylindiM;  |)ist()n  strotce  to  cutoff;  re- 
ductitm  of  pressure  from  commencement  of 
piston  stroke  to  cut-off;  piston  stroke  to 
release  :  terminal  |)ressure  ;  gain  in  economy 
due  expansion  ;  counter  pressure  if  engine 
is  workctl  non-condensing;  vacuum  as  real- 
ized in  the  cylinder,  if  engine  is  worked, 
condtiisiuK;  piston  stroke  to  exhaustclosure, 
usually  reckoiu'd  from  zero  point  of  stroke  ; 
value  of  cushion;  effect  of  lead  and  mean 
effective  ])rcssure  on  the  piston  iluring 
complete  stroke.  'I'lie  indicator  diagram, 
when  taken  in  connection  with  the  mean 
aiea,  and  stroke  of  piston,  and  revolutions 
of  crank  for  a  given  length  of  time,  enables 
us  to  ascertain  the  |)ower  developed  by  en- 
gine; and  when  taken  in  connection  with 
the  mean  area  of  piston,  i)ist(;n  speed,  and 
ratio  of  cylinder  clearance,  enables  us  to 
ascertain  the  steam  accounted  for  liy  the 
engine. 

"  The  mean  power  developed  by  engine 

compared  with  the  steam  delivered  by  the 

boilers,   furnishes    the   cost    of    power   in 

steam,  and,  when  compared  with  the  coal, 

furnish;.s  ^he  cost  of  the  power  in  fuel. 

"  The  diagram  also  enables  us  to  determine  with  precision  the  size  of  steam  and 

exhaust  ports  necessary,  under  given  conditions,  to  ecjualize  the  valve  functions  ;  to 

measure  the  loss  of  pressure  between  boiler  and  engine ;  to  measure  the  loss  <jf 

vacuum  between  condenser  and  cylinder ;  to  determine  leaks  into  and  out  of  the  cyl- 


37 


» ^5*.M«e«M*if 


inHer;  to  .ku-rmino  .dative  itfi-ct»  of  jacketed  and  unjacketcd  cylinder.;  and  to 
determine  cffLtts  ..f  exiuHMon  in  ..ne  cylinder,  and  in  two  or  more  cylinderH. 
— Hv  iKTiiiihsioii  of  Thomas  l»rii>,jun.,  editor  of  "The  Boiton  Jour- 
nal of  Commerce,"  we  publish  licre- 
vvith  one  iiccoimt  of  the  prjictical  ap- 
plication of  the  ituhcator,  wliich  will 
show  the  imi)ortancc  of  its  itppli- 
cation. 

"  The  diagrams  illustrated  in  the  present 
article  are  of  more  than  passing  intciest, 
and  wcrt!  taken  from  the  engine  of  a  man 
who  places  no  value  on  its  attachment.  It 
is  only  ne(  essary  to  say  to  the  experienced 
man,  that  the  diagrams  were  only  taken 
when  he  found  that  something  was  the  mat- 
ter which  his  engineer  could  not  manage  ; 
and  this  is  only  one  of  the  numerous  applica- 
tions of  the  value  of  the  indicator,  which 
the  expert  in  its  use  is  continually  meeting.  J2 
The  engine  in  ([uestion  is  a  Harris-Corliss,  • 
14  inches  diamete'  of  cylinder,  42  inches  p 
length  of  stroke,  60  revolutions  per  minute ; 
the  pressure  in  the  boiler  varying  from  65 
to  75  pounds.  The  diagrams  A  and  ^are 
from  the  different  ends  of  the  engine;  £ 
being  the  crank  end,  and  //  the  headend. 
/>'  is  one  of  these  peculiar-looking  diagrams 
which  we  freciuently  meet  with  in  actual 
practice,  more  esi)ecially  from  engineers 
who  know  exactly  how  to  set  their  valves 
by  a  scratch  or  prick  punch  mark ;  and  they 
can  tell  exactly  how  she  takes  steam  by 
watching  the  cut-off  slide.  The  engineer  in 
this  case  simply  had  to  give  it  up ;  and,  if 
he  had  gone  a  few  steps  farther,  his  engine 
wovild  have  run  the  other  way.  The  dia- 
gram ./  shows  three  lines  as  they  were 
taken  from  the  instruintnt,  and  they  are 
most  wretchedly  irregiilai  lines  too.  The  steam  line  is  as  full  of  humps  as  a  camel's 
bac  k,  and  the  notches  and  irregularities  are  the  exact  counteri)art  of  the  movements 
or  action  of  the  steam  as  it  is  admitted  to  the  cylinder.  The  admission  line  in 
itself  is  very  late.  The  steam  valve  commences  to  open  only  after  the  piston  has 
commenced  its  stroke.  It  does  not  open  fully  until  after  the  piston  has  travelled 
several  inches.  The  exhaust  will  be  seen  to  be  very  late,  both  upon  //  and  /i.  It 
is  comiiaratively  small  in  its  showing  u])i>n  A,  from  the  fact  that  the  diagram  A 
shows  a  very  mm.h  lighter  load  than  that  of  />'.     The  amount  of  power,  32.4-horse 


^ 


38 


*T!3r 


^ 


f\([\eriQa\)  St^am   (iau^?  ^o.,  BostoQ. 


power,  Kivtn  on  ./  it  the  mean  of  thrtc  line-*;  tin-  larncxt  amount  t)ting  plus  50, 
an<l  the  smalUst  only  22.     A  has  the  same  general  diitliiic  a*  /f :  l.ut  in  thi'*  lase 

. '  was  hcl  t<»  tut  off  at  li'»s  cli»iance  than  //  ,• 
<«o  that  A  l.«  only  a  siii^li-  line,  and  i*  dning 
thru  ipiartt  r»  tlu'  wi-rk  of  tlie  engine. 
'I'hf  line  in  the  ( asc  of  /,'  in  vciy  ha<l  in- 
(Ici'd.  The  valve  docs  nut  commence  to 
(i|)en  until  after  the  piston  has  iitatled  on  its 
return  str(»ite.  The  cut-off  is  very  badly 
defined,  and  might  lead  to  the  idea  that  the 
valves  were  badly  Kakinj;;  but  no  expct- 
ienccd  engineer  would  try  to  ascertain  this 
(pie»tir>n  until  the  valves  were  in  proper 
position.  'I'he  toe  at  the  enil  of  the  expan- 
sion, at  the  conuneiu  cment  of  the  exhaust 
line,  is  an  additional  amount  of  work 
thrown  away.  This  is  only  a  fair  specimen 
of  the  way  that  many  cnj;infcrs  get  their 
valves;  and  they  are  always  found  in  the 
.  hands  of  those  people  who  do  not  use  the 
•^  indicator,  and  who  frecjuently  make  the  as- 
O  sertion  that  they  do  not  believe  in  the  indi- 
'^  cator,  for  it  is  of  no  use.  All  such  are 
perfectly  welcome  to  their  belief;  and  their 
emi)loycrs  sometimes  change  their  minds 
when  the  engine  has  been  pro])erly  indicated 
and  adjusted  by  pcoiile  who  do  believe  in 
the  indicator,  and  who  know  how  to  apply 
it,  and  read  properly  its  r<^  ilts. 
"fand/^are  from  tht>  very  same  engine 
after  the  indicator  had  been  properly  ap- 
plied, and  the  needed  corrections  made  in 
the  motion  of  the  valves.  The  horse-power 
is  almost  idcntic.dly  the  same  in  both,  the 
fractions  being  very  small.  The  compres- 
sion is  almost  to  a  unit  the  same.  The 
admission  line  is  lost  in  the  proper  com- 
pressicm,  and  the  steam  line  is  carried  as 
straight  as  ,1  line.  The  line  of  exjjansion 
shows  V.  i>  little  loss,  and  the  diagram 
taken  altogether  is  a  very  good  product^n.  It  is  needless  to  say  that  a  very  con- 
siderable saving  of  fuel  resulted  as  the  dittrrencc  hctwct-n  the  engineer's  setting,  .•/ 
and  /i,  and  thatof  the  man  who  api.lied  tiie  indicator,  (  /).  These  diagrams  are  from 
actual  practice,  and  were  given  us  by  Mr.  Mosman  of  tlie  Americen  .Sieam  Gauge 
Company.  They  were  taken  with  40  springs,  and  the  engine  at  its  regular  work. 
Probably  the  (juestion  never  entered  the  head  of  the  engineer  in  charge  as  to  the 
result  of  the  use  of  steam  as  in  the  diagi-ims  ./  and  /.'.  The  steam  in  ./is  admitted 
in  all  sorts  of  tpiantity  in  the  cnd.nvor  of  the  regulator  to  reach  alter  and  equalize 
the  load  which  is  done  in  the  other  end  of  the  cylinder ;  lail  as  the  cut  olf  slides  are 


39 


■i* 


fim(^vr:aq  St^am  Qati^e  Qo.,  BostOQ.  ^^ 


set  at  B  to  cut  off  longer  than  is  necessary,  and  at  A  are  set  shorter  than  they 
should  be,  it  is  simply  impossible  for  the  regulator  to  adjust  the  difference  between 
them ;  for  the  difference  is  so  great  that  the  regulator  cannot  measure  it  by  the 
differential  strokes  of  the  cut-off  slides,  or  the  motion  which  is  given  them  through 
the  change  of  position  of  the  balls  on  the  governor.  In  this  case  the  crank  end  of 
the  engine  is  doing  more  than  double  that  of  the  head  end,  and  these  motions  of 
the  head  end  are  shown  in  the  irregular  steam  lines  by  its  race  after  the  other  end 
ot  the  engine ;  and  exactly  in  proportion  as  these  lines  differ  from  each  other,  was 
the  resistance  or  the  strain  upon  the  dif  .ent  parts  of  the  engine  ;  differing  at  each 
end  of  the  stroke,  making  120  times  per  ninute.  In  other  words,  the  engine  jumps 
120  times  a  minute  after  its  load,  and  the  regulator  is  simply  unable  to  adjust  the 
difference,  or,  in  other  words,  is  attempting  to  accomplish  an  impossibility.  The 
engine  in  this  case  is  using  something  like  forty  per  cent  or  more  steam  than  would 
be  necessary  when  properly  adjusted,  as  is  seen  in  the  figure  C  and  D  ;  and  this  is 
only  another  important  lesson  that  people  can  learn  if  they  will,  but  usually  only 
learn  when  they  are  obliged  to.  And  it  is  all  the  more  to  the  credit  of  the  indicator 
that  it  is  able  to  show  up,  in  the  hands  of  an  experienced  manipulator,  these  points 
where  pocket  value  is  the  point  attained ;  and  in  a  case  like  this  the  amount  of  coal 
burned  before  and  after  adjustment  is  a  factor  that  can  always  be  measured  in 
dollars  and  cents,  and  this  is  the  standard  of  too  many  steam-users  in  quite  an 
opposite  direction."  •    •.'/ 


USING  THE  INDICATOR. 

To  Attach  to  the  Cylinder. 

The  importance  of  the  nidicator  is  now  so  generally  recognized 
by  all  engine-builders,  that  nearly  all  first-class  engines  are  sent  from 
the  shops  with  cylinder  already  drilled  for  its  application.  When 
no  provision  has  been  trade  for  the  application  of  the  indicator, 
holes  must  be  drilled  and  tapped  with  not  less  than  half-inch  pipe 
tap,  in  such  position  in  the  side  of  the  cylinder,  that  when  the  piston 
is  at  the  ends  of  its  travel,  they  will  be  as  nearly  as  possible  in  the 
centre  of  the  clearance  space,  and  yet  not  be  obstructed  by  the  piston 
when  at  its  extremes  of  travel. 

In  drilling,  great  care  must  be  taken  not  to  allow  any  chips  to  get 
into  the  cylinder;  and,  when  the  heads  cannot  be  removed,  it  is 
better  to  turn  on  a  little  steam  as  the  drill  begins  to  enter,  in  order 
to  blow  the  cuttings  out. 

It  is  usually  most  convenient  to  remove  a  strip  or  two  of  the  lag- 
ging, and  drill  into  the  cylinder  at  the  top  or  back  side. 

Should  the  clearance  be  too  small  to  allow  of  this,  the  tap  inay  be 
made  directly  into  the  head,  which  it  is  desirable  to  avoid,  to  bring 
the  indicator  into  a  convenient  position  ;  the  object  being  always  to 


40 


■^ 


■  lag- 


*^ 


Pfnerioai)  St^am  (iau^^  Qo.,  Bostop. 


1«t 


have  the  indicator  connected  as  directly  as  possible  to  the  cylinder : 
and  in  all  cases  where  the  circumstances  will  permit,  the  indicator 
cock  should  be  screwed  into  the  cylinder  itself.  When  the  tap  is  on 
the  side  of  the  cylinder,  by  use  of  nipples  and  elbows,  which  we  can 
furnish,  the  indicator  can  be  brought  into  a  vertical  position,  the 
same  as  if  tapped  on  top  of  cylinder. 

We  do  not  recommend  the  use  of  a  half-inch  angle  valve  upon  the 
end  of  a  nipple,  into  which  the  indicator  cock  is  screwed.  Where 
the  arrangement  is  to  be  permanent,  it  is  much  better  to  have  an  in- 
dicator cock  for  each  end  of  the  cylinder,  which  may  be  neatly  cap- 
ped when  not  in  use,  preventing  anything  from  getting  into  the  pipe  ; 
offering  a  much  neater  appearance,  and,  what  is  of  more  consequence, 
less  obstruction  to  the  steam.  Obviously  the  most  proper  arrange- 
ment for  indicating  an  engine  is  to  have  an  instrument  upon  each 
end  of  the  cylinder,  from  which  simultaneous  diagrams  may  be  taken. 
This  arrangement  shows  its  advantages  where  engines  are  con- 
stantly changing  their  load,  and  where  it  is  desired  to  test  the  equali- 
zation of  the  work  between  the  two  ends  of  the  cylinder. 

When,  however,  a  single  indicator  is  to  be  used  upon  both  ends  of 
the  engine,  the  best  method  is,  to  connect  by  means  of  side  pipes 
and  a  three-way  cock  :  the  disadvantages  arising  fiom  this  indirect 
connection  being  more  than  counterbalanced  by  the  facility  with 
which  the  instrument  can  be  switched  from  one  end  of  the  cylinder  to 
the  other  without  loss  of  but  one  revolution,  and  without  disturbance 
of  the  connection  with  paper  drum,  and  by  the  fact  that  diagrams 

are  obtained  from  both  ends  of 
the  cylinder  on  the  same  card. 
The  turns  in  this  Three-way 
Cock  are  made  on  a  (juartcr- 
turn,  and  not  on  sharp  angles, 
as  in  the  old  style. 

PRICE    OF    THREE- WAY    COCK 
WITH    SLIP    .rOiyT    TO    AL- 
LOW EOti    EXrASSlOX,   ALL 
...       «      .  yiCKEL-PLATED    -    -    $6.<M 

FIG.  I2.-Three-Way  Cock. 

When,  however,  as  is  sometimes  done,  angle  valves  are  placed 

on  the  ends,  instead  of  elbows,  and  no  three-way  cock  at  the  centre, 
the  arrangement  is  in  its  most  objectionable  form,  and  the  resulting 
diagrams  will  present  an  appearance  similiar  to  that  produced  by 
deficient  lead  and  obstructed  induction. 


41 


,-  (\ 


/^/nerioai?  St^am  Qau^?  (;o.,  Bostoi?. 


It  is  unnecessary  for  us  to  explain  or  even  enumerate  the  different 
devices  that  have  and  can  be  used  for  this  purpose.  The  ingenuity 
of  the  operator  will  suggest  many  different  ways ;  but  the  essential 
requisite  for  such  a  device  is,  that  it  shall  give  to  the  paper  drum  a 
movement  which  is  a  perfect  duplicate  in  miniature  of  that  of  the 
piston  of  the  engine.  Many  arrangements  in  use  fail  to  do  this ;  in 
fact,  it  may  and  does  frequently  happen  that  the  distortion  is  so  con- 
siderable as  to  give  deceptive  records. 

Take,  for  instance,  the  most  common  and  easily  rigged  plan, — 
the  pendulum  lever  pivoted  to  any  convenient  fixed  support  above 
the  engine,  and  linked  at  its  lower  extremity  to  the  cross-head  by  a 
short  connecting-bar,  so  attached  as  to  incline  about  as  much  above 
a  horizontal  line  at  the  extremes  of  travel  as  it  does  below  at  mid- 
travel.  When  the  upper  end  of  this  pendulum  is  furnished  with  a 
segment  of  a  pulley  on  which  the  cord  leading  to  the  instrument 
winds  and  unwinds,  it  is  sometimes  called  the  *»Brumbo  pulley." 

With  this  arrangement,  the  drum  movement  will,  in  the  absence 
of  any  distortion  from  cord-stretching,  be  an  exact  copy  of  that  of 
the  lever ;  but  the  latter  will  not  be  an  exact  copy  of  the  piston 
movement.  The  connecting-bar  is  virtually  shortest  when  inclined 
upward  or  downward  :  hence  there  are  two  points  in  the  movement 
of  the  lever,  something  less  than  one-fourth  of  its  travel  from  its 
extremes,  where  it  is  farther  from  its  point  of  attachments  to  the 
cross-head  than  at  the  extremes ;  and  any  events,  as  the  cut-offs  for 
instance,  will  be  made  to  appear  unequal  when  they  are  really  equal. 
The  distortion  is  greatest  when  the  lever  and  the  connecting-bar  are 
short.  If  the  former  is  one  and  a  half  times  the  stroke,  and  the 
latter  half  or  more,  the  distortion  will  not  be  serious,  though  it  will 
exist.  A  pin  or  screw  in  the  lever  will  give  less  distortion  than  the 
segment,  provided  it  is  so  placed,  that,  when  the  piston  is  at  mid- 
stroke,  a  line  placed  between  it  and  the  pivot  of  the  lever  will  be  at 
right  angles  with  the  cord  ;  otherwise  the  movement  at  one  end  of 
the  travel  will  be  too  fast,  and  too  slow  at  the  other. 

The  most  correct,  and  at  the  same  time  most  convenient,  arrange- 
ment for  reducing  the  motion  of  the  cross-head  without  any  distor- 
tion whatever  is  the  pantograph. 


% 


42 


"^ 


w^ 


/^m^rieap  Steam  Qau^^  ^o.,  Bostoi^. 


^^ 


THE  PANTOGRAPH. 

We  are  the  on.y  parties  who  make  a  perfect  pantograph,  nicely 
made,  close-fitting,  and  positive  and  snug  motion. 

In  describing  it  and  its  mode  of  application,  we  quote  from  an 
article  by  "  Chordal "  in  the  "  American  Machinist,"  Dec.  27,  1879. 


FIQ.  13. 

"oRLiss's  Drum  Motion.  — I  call  this  a  Corliss  device,  because,  while  he 
_,  not  have  invented  it,  he  has  been  using  it  for  years,  and  is  the  only  person 
I  know  of  to  blame  for  its  being  known  and  used.  It  is  now  manufactured  and  for 
sale  by  the  American  Steam  Gauge  Company  of  Boston.  It  consists  of  a  lazy- 
tongs  system  of  levers.  The  long  levers  p.re  of  cherry  wood,  sixteen  inches  between 
centres,  one  and  one-eighth  by  five  sixteenths ;  those  marked  B  being  single  strips, 
and  those  marked  A  being  double  strips.  This  makes  the  thing  very  stiff  and  sub- 
stantial. The  pivots  should  be  got  up  in  good  style,  and  the  pivot  holes  bushed. 
The  hitch  strip  G  should  be  arranged  so  that  it  may  be  shifted  in  the  holes  A',  and 
bring  a  hitch  pole,  F,  in  a  line  passing  through  pivots,  CD.  The  end  pivots  C  and 
D  should  have  a  projection  below  of,  say,  two  inches,  with  the  end  somewhat 
pointed.  Any  one  who  attempts  to  make  one  of  these  things  will  have  fun.  The 
least  variation  in  the  location  of  the  pivot  holes  will  cause  the  levers  to  refuse  to 
act.  No  dimensions  are  essential :  and  if  the  thing  will  close  up  nicely  and  open  out 
nicely,  it  is  all  right ;  if  it  won't  do  both,  it  is  all  wrong.  The  engine  cross-head  must 
have  a  vertical  hole  in  it  somewhere,  so  that  pivot  Ccan  be  dropped  into  it.  A  stake 
must  be  set  in  the  floor  near  the  guides,  having  a  socket  for  the  pivot  />  in  its  top. 
The  stake  socket  must  be  level  with  the  cross-head  socket,  and  must  be  directly 
opposite  the  cross-head  socket  when  the  latter  is  at  mid-stroke.  The  indicator  cord 
is  hooked  to  the  centre  peg  /',  and  the  stake  should  set  at  such  a  distance  from  the 
guides  that  the  cord  will  lead  off  par-illel  with  the  guides.  Otherwise  a  guide  pulley 
will  be  called  for.  When  this  rig  is  in  motion,  every  point  on  a  line  cutting  CD 
has  a  true  motion  parallel  with  the  guides,  varying  in  distance  from  nothing  at  /J 
to  length  of  a  stroke  at  C.  It  is  only  necessary  to  hitch  the  cord  at  a  point  on  this 
line  which  will  give  the  right  amount  of  motion  to  the  cord.  This  point  will  be  near 
J),  and  within  the  range  of  adjustment  of  the  strip  6'.  This  is  as  neat  a  device  as 
could  be  wished  for.     I  have  seen  Mr.  Corliss's  men  hook  on  to  an  engine  running 


-IT 


?*.*; 


M 


mil 


43 


*? 


pmericar;  St^am  Qaa^e  Qo.,  Boetor;. 


^ 


at  a  good  gait,  without  stopping.  Mr.  Corli.ss,  I  think,  is  in  the  habit  of  putting  a 
permanent  socket  into  his  cross-head,  and  setting  a  nice  standard  in  a  floor  socket. 
In<licafor  cocks  are  kei)t  on  the  cylinder  at  all  times.  P'or  a  permanent  rig  on  a 
nice  engine,  the  stake  can  normally  sup))Lrt  a  neat  tahle-top  for  oil-cans  and  waste." 

PRICK 810.00 

A  variety  of  other  forms  of  attachments  can  be  and  are  sometimes 
used,  cording  to  circumstances;  but  the  ones  herein  described  are 
the  most  common  and  accurate. 

3:^^  On  p.  45  the  Indicator  is  shown  with  the  Pantograph  attached. 


44 


^ 


jutting  a 

r  socket. 

rig  on  a 

1  waste." 

.00 

letimes 
3ecl  are 


J^ 


fim^ricai?  St^am  gau^e  Qo.,  BostOQ. 


BACON'S  PATENT  PANTOGRAPH  ATTACH- 
MENT. 

[FROM  "TWENTY  YEARS  WITH  THE  INDICATOR."] 

This  simple  little  affair  is  the  invention  of  F.  W.  Hacon,  for  many  years  consult- 
ing and  indicating  engineer,  and  is  the  outcome  of  those  annoying  and  perplexing 
delays  and  hindcrances  that  are  so  often  found  by  the  indicating  engineer,  who  is 
travelling  from  place  to  place,  making  his  attachments,  and  putting  up  what  we 
usually!  lie  rinpine.     It  would  hardly  be  considered  a  credit  to  many  manu- 


FIQ.  15. 


facturing  concerns  if  the  real  paucity  of  mechanical  appliances  which  they  possessed 
were  known,  and  that  it  is  a  fact  that  many  of  them  have  not  even  a  hand-saw  or 
an  ordinary  nail-hammer. 

Before  the  lazy  tongs,  or  pantograph  as  it  is  now  known,  was  introduced,  we 
have  ourselves  frequently  spent  more  time  in  putting  up  or  down,  or  somewhere 


46 


w 


ptn^mar)  Steam  CJau^?  ^o.,  Bostorj. 


else,  the  pendulum,  or  some  other  ingenious  makeshift  to  properly  transmit  th 
reduced  motion  from  the  cross-head  or  trunnion  of  the  engine,  than  we  have  in 
indicating,  adjusting  and  finishing  up  all  the  rest  of  the  work.  It  was  to  obviate 
these  frequent  and  annoying  delays  that  our  friend  Bacon  invented  the  device  of 
which  we  are  now  to  speak. 

Fig.  i6  shows,  in  detail,  all  the  parts  of  this  attachment.  A,  H,  are  two  joined 
links  made  of  thin  sheot-iron  riveted  together.  The  short  piece  is  ujion  different 
sides  of  the  long  piece;  so  that  the  long  pieces,  ./  and  A,  when  locked  under  a  nut, 
will  bring  the  holes  through  which  the  pantogra])h  is  attached,  so  that,  while  one 
overlaps  the  other,  the  nut  under  which  the  long  pieces  arc  clamped  will  lie  in  a 
perfect  line  without  disturbing  the  grip  of  the  nut.  C  is  a  screw  which  can  be  either 
put  through  the  holes  shown  in  the  end  of  the  short  link  screwed  into  the  piece  /^ 
in  the  hole  in  the  end,  or,  if  the  pendulum  is  required,  it  can  be  attached  to  either 
one  of  the  holes  in  the  side  of  the  larger  part.  E  is  a  simple  thumb  nut,  which  can 
be  used  in  either  case.  The  whole  arrangement  can  be  carried  in  your  vest-pocket, 
or  in  a  coat-pocket,  without  any  trouble. 


^ 


Fig.  IS  shows  how  Mr.  Bacon's  attachment  is  applied  to  one  of  the  adjusting, 
nuts  which  steady  the  cross-head  on  the  brass  ways  ;  while  the  cross-head  lies  in  a 
horizontal  plane,  as  in  many  of  our  old-fashioned  horizontal  engines.  One  of  these 
adjusting-screws  is  lifted  a  little,  the  tv;o  long  links  are  shut  under  each  side  of  the 
screw  underneath  the  head,  and  the  head  then  screwed  down  upon  them,  making  it 
perfectly  rigid,  but  at  the  suie  time  not  altering  any  adjustment  of  the  engine. 
Here  a  little  point  must  be  borne  in  mind  by  the  party  who  is  applying  this  device. 
It  will  be  seen,  by  reference  to  Fig.  15,  that  we  have  attached  the  device  to  the  back 
end  of  the  cross-head  on  the  outside  of  the  guide,  and  that  we  must  allow  the  cross- 
head  to  travel  precisely  as  far  one  way  as  the  other,  and  must  take  the  end  of  that 
side  of  the  cross-head  to  which  we  have  made  the  attachment  for  our  centre  line, 
and  not  calculate  from  the  centre  nut  shown  on  that  side  of  the  cross-head.  Now, 
the  post,  the  top  of  which  is  shown  in  Fig.  17  which  supports  the  other  end  of  the 
pantograph,  must  be  exactly  square  with  the  portion  of  the  cross-head  to  which  we 
have  attached  the  pantograph,  when  the  cross-head  is  in  precisely  the  centre  of  its 
travel;  in  other  words,  we  must  allow  the  difference  between  the  central  nut  and 
the  ons  on  the  end,  as  shown,  from  which  to  obtain  our  central  line.    The  arms  of 


47 


/^m^rieai^  Steam  Cjau^^  (;o.,  Bostoi^. 


^ 


the  i)antograph  are  shown  shut  up  as  much  as  they  can  be  when  attached  properly. 
The  sui)i.ort  of  that  end  of  the  pantograj)!!  from  tlie  post  which  is  shown  at  its 
outer  arms,  and  the  cord-screw  in  the  short  cross-bar,  must  be  i)rfcisely  in  line  when 
the  pantograi)h  is  in  this  position,  else  the  diagram  is  worthless.  The  end  of  the 
post  must  be  high  enough  so  that  the  pantograph  lies  perfectly  easy,  and  without 
any  cross-friction  or  draugiit.  We  have  spoken  so  particularly  in  previous  lessons 
of  the  attachment  of  the  pantograph,  that  but  little  remains  here  to  be  said  except 
to  describe  the  motion. 


FIG.  17 


Fig.  17  shows  the  application  of  the  Bacon  attachment  to  a  perpendicular  guide, 
or  cross-head,  which  is  vertical.  In  this  case,  the  two  links  are  run  under  the  con- 
nection between  the  cross-head  proper  and  the  brasses  or  guides.  The  head  of 
the  post  is  also  shown.  * 


FIG.  18. 


Tn  Fig.  18  we  have  the  Corliss  guide,  where  the  links  are  put  under  the  adjusting 
screw  at  the  top.  This  may  be  done  by  boring  a  hole  into  the  cross-head,  and 
screwing  in  a  piece  of  three-eighths  round  iron,  the  outer  end  of  which  is  flattened 
and  has  an  eye  drilled  through  it,  then  dropping  the  tapering  stud  on  the  outer  end 
of  the  pantograph  into  the  eye  whenevei  it  is  desired  to  use  the  pantograph. 


\mk 


48 


"^ 


/^m^rloap  8team  (jau^^  §o.,  BoBtoQ. 


FIG.  19. 

Fig.  19  shows  the  attachment  in  which  the  ways  are  horizontal  1  but  we  have  not 
room  enough  to  spread  the  pantogriii)h  out,  as  in  Fig.  15  rtat ;  but  the  pantograph 
in  Fig.  19  is  supposed  to  be  vertical,  as  in  the  case  where  the  post  stands  near  the 
ways  of  the  engine  or  the  partition.  In  this  case,  the  piece  D,  Fig.  16,  is  made  use 
of;  and  the  screw  C,  or  the  thumb  nut,  is  attached  to  the  bottom  of  D. 


% 


FIG.  20. 

Fig.  20  shows  the  old-fashioned  pendulum  attached  io  3  vertical  guide  or  way. 
In  this  case,  a  little  slot  in  the  lower  end  of  the  pantograph  is  necessary.  The  links 
may  not  necessarily  be  used  in  the  position  shown,  but  may  be  brought  up  at  right 
angles,  leaving  the  slot  to  make  allowance  for  the  circle  dest  libed. 

This  attachment  avoids  drilling,  tai)ping,  taking  out  the  screws  that  confine  the 
gibs,  or  defacing  the  engine  anywhere.  On  slow-moving  or  condensing  engines, 
these  attachments  can  be  applied  so  that  the  pantograph  can  at  any  time  be  hooked 
on  while  running ;  and  diagrams  can  be  taken  from  the  high  or  low  pressure 
cylinder,  from  the  pumps,  stand-pipe,  or  anywhere  that  is  necessary. 

It  is  a  simple  little  convenience ;  and,  as  we  have  found  within  the  past  few  months, 
it  saves  a  great  deal  of  vexation  and  delay,  and  insures  more  accuracy  in  the  work, 
if  only  a  little  pains  are  taken.  One  point  must  also  be  observed  by  parties  in 
using  the  pantograph  ;  that  is,  to  allow  a  little  leeway  between  the  carrying-pulleys 
of  the  indicator  and  the  cord  peg  of  the  pantograj)h  :  for  we  have  seen  some  very 
awkward  mistakes  made  by  allowing  the  cord  to  sag  a  little,  and  to  strike  the  screws 
in  the  ends  of  the  short  arms,  which  give  a  twitch  to  the  indicator  cord  ;  and  we 
have  been  caught  ourselves  making  saw-teeth  on  the  expansion  line  of  a  card  by 
this  very  apt-to-occur  little  matter. 

Bacon's  Attachment,  patented  July  25,  1882,  is  solely  manufactured  and  for  sale 
by  the  American  Steam  Gauge  Company  of  Boston.  It  costs  very  little,  and  it  is 
certainly  a  labor-saving  and  an  annoyance-preventing  device. 


PRICE  OF  BACON'S  PATENT  ATTACHMENT  FOR  PAN- 
TOGRAPH  


•e.ffo 


49 


;)merioa9  St^am  QauQe  ^o.,  Bostop. 


^^ 


TO   TAKE  A  DIAGRAM. 

Connccdrifr.  Cord. —The  indicator  hhoiild  he  connected  to  the 
engine  cross-head  hy  as  short  a  length  of  cord  as  |)(».ssil)le.  Cord 
having  very  little  stretch,  such  as  accompanies  the  instrument, 
should  he  useil ;  and,  in  cases  of  very  long  lengths,  wire  should  be 
used. 

Ti  e  short  piece  of  cord  connected  with  the  indicator  is  furnished 
with  a  hook  ;  and  at  the  end  of  the  cord,  connected  with  the  engine, 
a  running  loop  can  he  made,  hy  means  of  the  small  plate  sent  with 
each  instrument,  in  the  manner  shown  in  the  accompanying  cut ; 
hy  which  the  cord  can  be  adjusted  to  the  proper  length,  and 
lengthened  or  shortened  as  required. 


FIQ.  21. 

Selecting  a  Spring. — It  is  not  advisable  to  use  too  light  a  spring 
for  the  pressure.  Two  inches  are  sufficient  for  the  height  of  diagram, 
and  the  instrument  will  be  less  liable  to  damage  if  the  proper  spring 
is  used.  The  gauge  pressure  divided  by  2  will  give  the  scale  of 
spring  to  give  a  diagram  two  inches  high  at  that  pressure. 

For  rule  to  determine  maximum  pressure  for  each  spring,  and 
directions  to  change  spring,  see  p.  9. 

To  attach  a  Card. — This  may  be  done  in  a  variety  of  ways, 
either  by  passing  the  ends  of  it  under  the  spring  clips,  or  by  folding 
one  end  under  the  left  clip,  and  bringing  the  o*:her  end  around 
under  the  right ;  but,  whatever  method  is  applied,  care  should  be 
taken  to  have  the  card  rest  smoothly  and  evenly  on  the  paper  drum. 

Now  attach  the  cord  from  the  reducing-motion  to  the  engine ;  but 
be  certain  the  cord  is  of  the  proper  length,  so  as  to  prevent  paper 
drum  from  striking  the  inner  stop  in  drum  movement  on  either  end 
of  the  stroke. 

Tension  of  Drtim  Spring. — The  tension  of  the  drum  spring 
should  be  adjusted  according  to  the  speed  of  the  engine ;  increasing 
for  quick  running,  and  loosening  for  slower  speeds. 

The  steam  should  not  be  allowed  into  the  indicator  until  it  has 
first  been  allowed  to  escape  through  the  relief  on  side  of  cock,  to  see 
if  it  is  clean  and  dry.  If  clean  and  dry,  allow  it  into  the  indicator, 
and  allow  piston  to  play  up  and  down  freely. 


50 


im 


pos 
pai 


pel 


and 


0 


r 


/tm^ricaip  8CQam  Qau^e  Qo..  Bostop. 


^ 


Before  takinf^  liiiii^tuim,  tiiiii  the  liaiulU-  «>fc()tk  t(i  ;•  hoH/ontal 
position,  Ko  iis  to  sluit  olV  steam  tVoin  piston,  an«l  ••ppl)  |>encii  to  the* 
paper  to  take  the  atin(»spheiic  Mne. 

In  apphinjir  pencil  to  the  carJ^  always  use  the  horn-handle 
screw,  to  rej^uhite  pressure  ol"  pencil  upon  paper  to  pnxhice  as  fine 
a  line  as  possible. 

After  the  atniospherif  line  is  taken,  turn  on  steam,  and  press  the 
pencil  ajjainst  card  durinj;  r»ne  revolution. 

When  the  load  is  varying^  and  the  average  horse-power  reipiired, 
it  is  better  to  allow  the  pencil  to  remain  during  a  number  of  revolu- 
tions, and  to  take  the  mean  enictive  pressure  from  the  card. 

Remove  card  after  dia^jram  has  been  taken  ;  atid  on  the  back  of 
card  make  note  of  the  following  particulars,  as  far  as  conveniently 
obtainable:  — 

18 


Barometer  read*. 


DIAGRAM    from    M Engine. 

Diameter  of  Cylinder Built  by 

Length  of  Stroke .. 

Revolutions  per  Minute 

Preuure  of  Steam,  in  lbs. ,  in  Boiler 

Position  of  Throttle  Valve 

Vacuum  per  Gauge,  in  inches 

Temperature  of  Hot  Well 

Scale  of  Spring 

Inside  Diameter  of  Feed  Pipe... 

"  "  "     Exhaust  Pipe 

Valves 


Pressure 


Throttle... 
..Regulator. 


REMARKS 


After  sufficient  number  of  diagrams  have  been  taken^  remove 
the  piston,  spring,  etc.,  from  the  indicator,  wiiile  it  is  still  upon  the 
cylinder  ;  allow  the  steam  to  blow  for  a  moment  throuj^h  the  indicator 
cylinder;  and  then  turn  attention  to  tha  piston,  spring,  and  all 
movable  parts,  which  must  be  thoroughly  wiped,  oiled  and  cleaned. 
Particular  attention  should  be  paid  to  the  springs,  as  their  accuracy. 
will  be  impaired  if  they  are  allowed  to  rust ;  and  great  care  should 
be  exercised  that  no  grit  or  substance  be  introduced,  to  cut  the 
cylinder,  or  scratch  the  piston.  .         ; 

Be  careful  always  not  to  bend  the  steel  bars  or  rods.  : 


51 


11 


w- 


/^merioaQ  St^am  (iau9?  <5o.,  BostoQ. 


"t! 


The  lu'al  of  the  Mcain  blown  tlironuli  thccvliiuliior  tlii- indicator 
will  be  toimd  to  li;i\c  driid  it  piifcitly,  and  the  instrnnunt  may  be 
|)iit  to^^cthir  with  (he  assnranci'  thai  it  is  all  ri-ady  lor  use  when 
rc»|nired.     Otiui   items  of  precaiilnjii  should  be  borne  in  mind  (see 

Any  enjfineer  t.di  easily  repeat  this  operation  without  turther 
iuhtiuction. 

Ding  ra  »i  A  nalyn  In . 

The  Ibllowing  definitions  have  been  ^jiven  to  the  diflerent  parts 
r)f  the  diagram  proper,  an<l  to  lines  added  as  recpiired  for  purposes 
of  analysis.  The  same  letters  refei  to  the  same  parts  on  ditlerent 
diagrams. 

Figs.  21  an<l  J3  are  from  throttling-engines;  the  former  represent- 
ing good  performances  for  that  class  of  engine,  and  the  latter  ii.  some 
respects,  which  the  engineer  will  readily  recognize,  bad  perform- 
ances. 

Figs.  24,  25  and  26  are  from  automatics;  Fig.  24  representing  what 
is  now  considered  rather  too  light  a  load  for  best  practical  economy, 
Fig.  25  about  the  best  load,  and  Fig.  26  is  from  a  condensing  enj^Mne. 

Line  AB  is  the  induction  line,  anil  BC  the  steam  line;  both 
together  representing  tlie  whole  time  of  admission. 

C  is  about  the  point  of  cut-oH",  as  nearly  as  can  be  determined  by 
inspection.  It  is  mostly  anticipated  by  a  partial  fall  of  pressuri.' due 
to  the  progressive  closure  of  tlie  valve. 

The  usual  method  is,  to  locate  it  about  where  the  line  changes  its 
direction  of  curvature. 

CI)  is  the  expansion  curve. 

D  is  the  point  of  exhaust. 

DE  is  the  exhaust  line,  which  should  begin  near  the  end  of  the 
stroke,  and  terminate  at  the  end  of  the  stroke,  or,  at  least,  before 
the  piston  has  moved  any  consiflerable  distance  on  its  return  stroke. 

The  principal  defect  of  Fig.  23  is,  that  this  line  occupies  nearly 
all  of  the  return  stroke.  EF  is  the  back  pressure  line,  which  in 
non-condensing  engines  should  be  coincident  with,  or  but  little 
above,  atmospheric  pressure.  In  Fig.  26  it  is  lielow  the  atmos- 
pheric line  to  the  extent  of  the  vacuum  obtained  in  the  cylinder. 
Some  authorities  would  call  it  the  vacuum  line  in  Fig.  26,  but  that 
name  properly  belongs  to  a  line  representing  a  perfect  vacuum. 


Sa 


f\mr\QaT)  5t^am  Qau^^  (;o..  Boetoij. 


/''  1h  the  point  of  i-xliiiiist  iIomm.-  («,lij;hi|y  iinlicip.iliil  l.y  lisr  of 
pressure),  and  /vl  the  lonipreshion  tnrve,  \\hi»li,  joininjj  the 
juhnihsion  line  .it  ,1,  lompUtes  the  diajjrani  j)roper,  forming;  iul<»»e(I 

Ci  C  is  the  atmospheric  line  traced  when  the  piston  of  the  indicator 
is  subject  to  atmospheric  pressure,  ahove  and  Itelow  alike.     Some 


1 


pull  the  cord  by  hand  when  tracing  it,  to  make  it  longer  than  the 
diagram.     J///  is  the  vacuum  line,  which,  when  required,  is  located 


S3 


i 


¥ 


pmericai}  Steam   (Jau^e  Qo.,  BostOQ. 


by  measuicnicnt  siicli  a  distance  below    the  atmosplieric  line  as  to 
represent  the  atmospheric  pressure  at  the  time  and  place,  as  nearly 


as  can  be  ascertained.  The  mean  atmospheric  pressure  at  the  sea 
level  is  14.7  pounds.  For  higher  altitudes,  the  corresponding  mean 
pressure  may  be  found  by  multiplying  the  altitude  by  .00053,  ^"^^ 
subtracting  the  product  from  14.7.  When  a  barometer  can  be  con- 
sulted, its  reading  in  inches  multiplied  by  .49  will  give  the  pressure 
in  pounds. 

/  is  the  clearance  line,   representing,   by  its  distance    from    the 
nearest  point  of  the  end  of  the  diagram  at  the  admission  end,  as 


«* 


54 


B^ 


f\([\(^T\Qaq  Steam  Qau^^  $o.,  805^09. 


compared  witli  tlic  vvlioic  lcn},'iii,  the  whole  volume  of  clearance 
known  to  be  present.  Its  use  is  mainly  to  assist  in  constructing  a 
theoretical  expansion  curve  by  which  to  test  the  accuracy  ot  the 
actual  one. 

Calculating-  Mean   Effective   Pressure. —  Since  the  simplifica- 
tion and  popularization  of  the  planimeter,  no  engineer   who   has 


1 


occasion  to  compute  the  "indicated  horse-power"  (IHP)  of  engines 
should  be  without  one:  for,  if  properly  handled,  the  results  obtained 
by  them  are  more  accurate  and  more  quickly  obtained  than  by  any 
other  process. 


55 


^ 
^^^ 


III 

>;   i 

!! 


at.. 


/^m^ricaQ  Stea/n  Cjau^^  (^o.,  BostoQ. 


The  diagram  is  pinned  to  a  smooth  board  covered  with  a  sheet  of 
smooth  paper,  tlie  pivot  of  the  leg  pressed  into  the  board  at  a  point 
which  will  allow  the  tracing-point  to  be  moved  around  the  outline 
of  the  diagram  without  Icjiiuing  unnecessarily  extreme  angles 
between  the  two  legs,  and  a  slight  indentation  made  in  the  line  at 
some  point  convenient  tor  beginning  and  ending;  for  it  is  vitally 
important  that  the  beginning  and  ending  shall  be  at  exactly  the  same 
point. 

The  reading  of  the  wheel  is  taken,  or  it  is  placed  ,t  zero,  and  the 


»/f 


in 
O 

iZ 


tracing-point  is  passed  carefully  around  the  diagram,  following  the 
lines  as  closely  as  possible,  moving  right-handed,  like  the  hands  of 


^i^ 


56 


Jl^ 


;ii 


/Im^ricai)  Steam  Cauf^  ^o..  Bostoi). 


^ 


a  watch.  The  readiiifi^  ohtainof!  (by  fln(lin<;  tht-  iHtVtMcuce  hctAveon 
the  two  if  the  wheel  has  not  l)ee!\  placed  at  zero)  is  the  area  of  the 
diagram  in  square  inches,  which,  multiplied  bv  tiic  scale  of  the  dia- 
gram, and  divided  by  its  length  in  inches,  gives  the  mean  etVective 
pressure. 

TAe  Process  of  finding  the  Mean  Effective  Pressure  by  Ordi- 
nates.  —  Fig.  25  is  too  well  known  to  require  any  detailed  explana- 
tion at  our  hands;  but  we  wish  to  call  attention  to  a  frecjuent  niis- 


2 


take,  namely,  making  all  the  spaces  equal.  The  end  ones  should 
be  half  the  width  of  the  others,  since  the  ordinates  stand  for  the 
centres  of  equal  spaces. 


57 


/)f[\eriQa9  Steam  Qau^e  ^o.,  Bostoi;. 


Ten  is  the  most  convenient  and  usual  number  of  ordinates,  though 
more  would  g^ve  more  accurate  results.  The  aggregate  lengf:h  of 
all  the  ordinates  (most  conveniently  measured  consecutively  on  a 
strip  of  paper)  divided  by  their  number,  and  multiplied  by  the  scale 
of  diagram,  will  give  the  mean  effective  pressure. 

A  quick  way  of  making  i  :lose  approximation  to  the  mean  effec- 
tive pressure  of  a  diagram  Is,  to  draw  line  aiy  Fig.  27,  touching  at 
a,  and  so  that  space  d  will  .qual  in  area  spaces  c  and  e,  taken 
together,  as  nearly  as  can  be  estimated  by  the  eye. 

Then  a  measure,  y,  taken  at  the  middle,  will  be  the  mean  effec- 
tive pressure.  With  a  little  practice,  verifying  the  results  with  the 
planimeter,  the  ability  can  soon  be  acquired  to  make  estimates  in  this 
way  with  only  a  fraction  of  a  pound  of  error  with  diagrams  repre- 
senting some  degree  of  load.  With  very  high  initial  pressure  and 
early  cut-off,  it  is  not  so  available. 


FIG.  27. 

TAe  Indicated  Horse- Power. — IHP  is  found  by  multiplying 
together  the  area  of  the  piston  (minus  half  the  area  of  the  piston-rod 
section  when  gi-^at  accuracy  is  desired),  the  mean  effective  pressure, 
and  the  travel  o^  the  piston  in  feet  per  minute,  and  dividing  the  pro- 
duct by  33,000. 

It  is  sometimes  convenient  to  know  the  HP  constant  of  an  engine 
which  is  its  HP  for  one  revolution  at  one  pound  mean  effective 
pressure.  .,:<     .     , 

This  multiplied  by  the  mean  effective  pressure,  and  by  its  number 
of  revolutions  per  minute,  gives  the  IHP. 


» ft' 


58 


/^merieai;  8t^am  (jau^e  ^o.,  Bo8to9. 


THEORETICAL  CURVE. 

Testing  Expansion  Curves.  —  It  is  customary  to  assume  that 
steam,  in  expanding,  is  governed  by  what  is  known  as  Mariotte's 
law,  according  to  which  its  volume  and  pressure  are  inversely  pro- 
portional to  each  other.  Thus,  if  i  cubic  foot  of  steam  at,  say,  loo 
pounds  pressure  be  expanded  to  3  cubic  feet,  its  pressure  will  fall  to 
50  pounds,  and  proj) ortionately  for  all  other  degrees  of  expansion. 
The  pressures  named  are  ''total  pressures;"  that  is,  they  are 
reckoned  from  a  peifect  vacuum. 

A  theoretic  expansion  curve  which  will  conform  to  the  above 
theory  may  be  traced  by  the  following  method. 


FIG.  28. 

Referring  to  Fig.  28,  having  drawn  the  clearance  and  vacuum 
lines,  as  before  explained,  draw  any  convenient  number  of  vertical 
lines,  I,  2,  3,  4,  5,  etc.,  at  equal  distances  apart,  beginning  with 
the  clearance  line,  and  number  them  as  shown. 

Decide  at  what  point  in  the  expansion  curve  of  the  diagram  you 
wish  the  theoretic  curve  to  coincide  with  it.     Suppose  you  choose 


59 


i 


Ml|lil'!)l>i|ll>* 


md.',m^6m 


_.    - 


4^ 


firnvnoaQ  8tpa.5    Ca<J9?  ^o-  Bostoi?.  ^'^^ 


line  lo,  on  whic!  you  find  the  indicated  pressure  to  be  25  pounds. 
Multiply  this  pressure  by  the  number  of  the  line  (10),  and  divide 
the  product  (250)  by  the  numbers  cfeach  of  the  other  lints  hi.  suc- 
ccssion.  Ti  j  quoJcnts  will  He  the  pressures  to  be  set  o!)  oa  tho 
lines.  Thus,  250  divided  by  o  gives  27.7,  the  pressure  vn  Iht-  t»  ; 
and  so  for  all  the  others. 

The  same  curve  may  ali^o  be  traced  by  several  ge<  metric  ViCthuCi, 
one  of  which  is  as  follows,  referring  to  Fig.  :.(j  :  — 


B  n 


c 


FIG.  29. 


Having  drawn  the  cleamnce  and  vacuum  lines  as  before,  select 
the  desired  point  of  coincidence,  as  a,  from  which  draw  the  per- 
pendicular a  A.  Draw  AB  at  any  convenient  height  above  or  near 
the  top  of  the  diagram,  and  parallel  to  the  vacuum  line  DC  From 
A  draw  AC,  and  from  a  draw  ad  parallel  to  DC ;  and  from  its 
intersection  with  AB  erect  the  perpendicular  6c,  locating  the  the- 
oretical point  of  cut-ofl'  on  AB.  From  any  convenient  number  of 
points  in  AB  (which  may  be  located  without  measurement),  as 
£,  F',  G,  H,  draw  lines  to  C,  and  also  drop  perpendiculars  Ee, 
Ff,  Gg,  Hh,  etc.  From  the  intersection  of  ^C  with  be,  draw  a 
horizontal  to  e,  and  the  same  for  each  of  the  other  lines  FC,  G  C, 
HC ;  establishing  points  e,  f,  g,  h,  in  the  desired  cui"ve.  Any 
desired  number  of  points  may  be  found  in  the  same  way. 


•W 


60 


»^ 


w 


F 


f\fr\qr'\Qai)  5team  Qau^^  $o.,  Bojtoi^. 


But  this  curve  does  not  correctly  represent  the  expansion  of  steam. 
It  would  do  so  if  the  t,teani  durinj^  expansion  remained,  or  was 
maintained  at  a  uniftjrm  temperature  ;  hence  it  is  called  the  isother- 
mal curve,  or  curve  of  same  temperature.  But,  in  fact,  steam  and 
all  other  elastic  fluids  fall  in  temperature  during  expansion,  and  rise 
during  compression  :  and  this  change  of  temperature  augments  the 
change  of  pressure  slightly ;  so  that,  if,  as  before  assumed,  a  cubic 
foot  of  steam  at  loo  pounds  total  pressure  be  expanded  to  two  cubic 
feel,  the  temperature  will  fall  from  nearly  328"  to  about  278°,  and 
the  pressure,  instead  of  falling  tj  fifty  pounds,  will  fall  a  trifle  below 
48  pounds. 

A  curve  in  which  the  pressure  due  to  the  combined  ertects  of 
volume  and  resulting  temperature  is  represented,  is  called  thi; 
adiabatic  curve,  or  curve  of  no  transmission ;  since,  if  no  heat  is 
transmitted  to  or  from  the  fluid  during  change  of  volume,  its  sensible 
temperature  will  change  according  to  a  fixed  ratio,  which  will  be 
the  same  for  the  same  fluid  in  all  cases. 

We  need  not  attempt  to  give  any  of  the  usual  methods  of  tracing 
the  adiabatic  curve,  since  the  isothermal  curve  is  the  one  generally 
used  for  the  purpose.  And,  while  it  is  incorrect  in  that  it  does  not 
show  enough  change  or  pressure  for  a  given  change  of  volume,  the 
great  majority  of  actual  diagrams  are  still  more  incorrect  in  the  same 
direction ;  so  that,  when  a  diagram  conforms  to  it  as  closely  as  the 
one  used  in  our  illustrations,  it  is  considered  a  remarkably  good 
one. 

A  srfficiently  close  approximation  to  the  adiabatic  curve  to  enable 
the  Uv-  professional  engineer  to  form  an  idea  of  the  difference 
between  the  two,  may  be  pix>duced  by  the  following  process  :  - — 

Taking  a  similar  diagram  to  that  used  for  the  foregoing  illustra- 
tions, we  fix  on  a  point  A  near  the  terminal,  where  the  tv>tal  pressure 
is  25  pounds..  As  before,  this  point  is  chosen  in  order  that  the  two 
curves  may  coincide  at  that  point.  Any  other  point  might  have 
been  chosen  for  th<?  point  of  coincidence  ;  but  a  point  in  that  vicinity 
is  generally  chosen,  so  that  the  residt  will  show  the  amoimt  of  power 
that  should  K'  obtained  from  the  existing  terminal.  This  point  is 
3.3  inches  from  the  clearance  line,  and  the  volume  of  25  pounds  is 
99^  ;  that  is,  steam  at  that  pressure  has  996  times  the  bulk  of  water. 
Now,  if  we  divide  the  distaiice  of  A  from  the  clearance  line  by  996, 
and  multiply  the  quotient  by  each  of  the  volumes  of  the  other  press- 


61 


;ij; 


/tm^rioar;  Steafn  CauQ^  ^o.,  BoetoQ. 


^ 


urcs  indicated  by  sitnilnr  lines,  the  pruducts  will  he  the  respective 
lengths  of  the  lines  measured  from  the  clearance  line ;  the  tlesired 
curve  passing  througii  their  other  ends.  Thus,  the  (piotient  of  the 
first  or  25-pound-pressure  line  divided  by  996  is  .003313  ;  this  mul- 
tiplied by  726,  the  volume  of  35  pounds  pressure,  gives  2.4  the 
length  of  the  35-poun(l-prcssure  line;  and  so  on  for  all  the  rest. 
On  applying  either  of  the  above  theoretical  curves  to  diagrams,  it 


m 

m 

(0 
iZ 


will  be  found  that  some  are  much  .nore  accurate  than  others,  even 
amongst  the  same  build  of  engine,  embodying  the  same  grade  of 
workmanship.  As  a  general  rule,  those  from  large  engines  will  be 
more  correct  than  from  small  ones,  and  high  or  tolerably  high  piston 
speeds  than  slow.     Also,  efficient  covering  for  cylinders  and  steam- 


62 


M*.  o   o 


P(r\ermr)  5t^am  (Jau^?  ^o.,  Bostoi?. 


pipes  to  prevent  rndiiition  antl  condensation  improves  thttn  in  this 
respect. 

The  character  of  the  imperfections  revealed  hy  this  means  is  pretty 
niiiformly  the  same;  namely,  too  high  a  terminal  pressure  for  the 
point  of  cut-oti'.  The  first  part  of  the  curve  formed  is  }{enerally  the 
most  correct,  nearly  all  the  inaccuracy  making  its  appearance  in 
the  later  half. 

The  f^enirally  accepted  explanation  is,  that  the  incominj^  steam  '••'•. 
partly  condensed ;  but  when  the  pressure  is  partly  removed,  antl  the 
exj)andL'(l  steam  begins  to  be  exposed  to  that  part  of  the  cylinder 
which  has  been  recently  heated  by  the  steam  which  has  just  before 
acted  on  the  other  side  of  the  piston,  the  water  resulting  from  such 
condensation  is  re-evaporated  into  steam,  which  auguments  the  ter- 
minal piessiire,  sometimes  to  the  extent  of  five  or  more  pounds, 
ihit  valve  leakage  has,  no  doubt,  often  much  to  do  with  producing 
the  fault,  espec  iaily  when  it  appears  to  any  considerable  degree  in 
the  case  of  engines  of  good  size  and  speed,  with  well-protected 
cylinders. 

Water-consumption  Calculations.  —  An  engine  driven  by  water 
instead  of  steam,  at  a  pressure  of  one  pound  per  square  inch,  would 
require  859,375  pounds  per  HP  per  hour ;  the  water  being  of  such 
temperature  and  density  that  one  cubic  foot  would  weigh  62^ 
pounds.  If  the  mean  pressure  were  more  than  one  pound,  the  con- 
sumption would  be  proportionately  less;  and,  if  steam  were  used, 
the  consumption  would  be  as  much  less  as  the  volume  of  steam  used 
was  greater  than  an  equal  weight  of  water.  Hence,  if  we  divide 
the  number  859,375  by  the  mean  effective  pressure  and  by  the 
volume  of  the  terminal  pressure,  the  result  will  be  the  theoretical 
rate  of  water  consumption  in  pounds  per  IHP  per  hour. 

For  the  terminal  pressure,  we  may  take  the  pressure  at  any  con- 
venient point  in  the  expansion  curve  near  the  terminal,  as  at  A., 
Fig.  30,  in  which  case  the  result  found  must  be  diminished  in  he 
proportion  that  the  portion  of  stroke  remaining  to  be  made,  j\a, 
bears  to  the  whole  length  of  the  stroke  ab  ;  and  it  may  also  be 
diminished  by  the  proportion  of  stroke  remaining  to  be  made  after 
the  pressure  at  A  has  been  reached  in  the  compression  curve  at  B. 
In  other  words,  AB  is  the  portion  of  the  stroke  al>  during  which 
steam  at  the  pressure  at  A  is  being  consumed.  Hence  the  result 
obtained  by  the  above  rule  is  multiplied  by  AB.,  and  the  product 
divided  by  ab. 


63 


i';i 


w^ 


fitti^n^ar)  8t^am  ^aa^e  Qo.,  603(09. 


"^ 


volume  is  996.     Thcn- 


:  =  22.94  pounds  water  per  IHP  per 


To  illustrate,  Huppose  the  mean  etVective  presnure  of  the  diagram 
to  be  37.6  pounds,  and  the  pressure  at  A  25  pounds,  of  ivhich  the 

37.()X99^>' 

hour,  the  rate  that  would  be  due  to  using  an  entire  cylinder  full  of 

steam  at  25  pounds  pressure  every  stroke.     But  as  the  period  of 

consumption  is  represented  by  BA,  6a  being  the  stroke,  the  follow- 

,.       .            .     ,    22.94x3.03  .  ,    . 

mg  correction  is  required  : ^-^ — ^ — ^  =  20.15  ;  3.03   mches  bemg 

3-45 
the  portion  BA,  and  3.45  inches  being  the  whole  length  6a.     This 

correction  allows  for  the  eflects  of  clearance  as  well  as  compression, 


since,  i*"  more  clearance  had  existed,  the  pressure  at  w4  would  not 
have  been  reached  till  later  in  the  stroke,  and  the  consumption  line 
If  A  would  have  been  longer. 

But  such  a  rate  can  never  be  realized  in  practice.  Under  the 
best  attainable  conditions,  such  as  about  the  load  indicated  on  the 
diagram,  or,  more,  on  a  large  engine  with  steam-tight  valves  and 
piston,  and  well-protected  cylinder  and  pipes,  the  unindicated  loss 
will  seldom  V>e  less  than  10  per  cent;  and  it  will  be  increased  by 
departure  from  any  of  the  above  conditions  to  almost  any  extent. 
It  will  increase  at  an  accelerating  ratio  as  the  load  is  diminished,  so 
that  such  calculations  applied  to  light-load  diagrams  would  be 
deceptive  and  misleading;  in  fact,  they  have  but  little  practical 
value  except  when  made  for  comparison  with  tests  of  actual  con- 
sumption, for  the  purpose  of  determining  the  amount  of  loss  under 
given  conditions. 


FIG.  31. 

J^/pe  Diagrams.  —  Sometimes  when  considerable  loss  of  press- 
ure appears  on  comparing  that  shown  by  the  gauge  with  the  highest 
initial  pressure  shown  by  the  diagram,  it  will  be  found  very  instruc- 


64 


^ 


\t 


f(lf\er'iQ^[)  $t^9a\  Qaa^^  ^o..  BostoQ. 


tivi'  to  connect  the  indicator  witu  the  Kti-am  pipe  in  addition  to  itn 
UHiial  connections.  A  |  inch  or  ^  inch  pipe  will  he  Nuthcii-nt  for 
the  purpose,  with  a  valve  or  cock  as  close  to  the  indicator  as  c*»n- 
venient.  Me|V»re  or  after  taking  the  cylinder  dia^^rams  steam  is 
admitted  to  the  instrument  from  the  steam  pipe  and  the  pencil 
applied,  when  a  diagram  sitiiilar  to  that  shown  ahove  the  cylinder 
diagrams  in  Fig.  31  is  produced.  In  that  figure  it  shown  that  there 
is  scarcely  any  loss  of  pressure  between  the  pipe  iitui  the  piston,  all 
tlie  loss  being  in  the  pipe  at  the  beginning  of  the  stroke,  though  a 
little  .i-sfi  of  pressure  between  the  pipe  and  piston  appears  as  the 
point  uf  cut  otl  is  approached. 

Sometimes,  —  fre(|uently,  in  fact,  —  the  pressure  in  the  pipe 
rises  above  that  in  the  boiler  for  a  moment  alter  cut  otf,  but  such 
extra  pressure  will  be  readily  recognized  by  its  falling  again  before 
the  next  admission.  IMiis  is  due  to  tlic  momentum  of  the  steam 
when  suddenly  cut  otl',  and  its  etVects  will  be  greatest  with  long, 
straight  pipes. 

When  the  pipe  diagram  is  above  and  clear  of  the  cylinder  dia- 
grams at  all  points,  the  space  separating  them  is  the  measure  of  the 
loss  of  pressure  due  to  passing  tludugh  the  cylinder  ports  and  all 
passages  between  the  point  from  which  it  is  taken  and  the  piston, 
while  the  variations  of  pressure  in  the  pipe  diagram  indicate  the 
loss  due  to  passing  through  the  pipe,  allowance  being  made,  as 
above  explained,  for  the  rebound  ol  pressure  above  that  in  the 
boiler,  when  it  is  shown  to  exist. 


We  shall  he  pleased  to  furnish  electrotypes  of  the  Thompson 
Improved  Indicato^r^  or  any  other  instrument  illu  trated  in  this 
catalogue  to  parties  desiring  them  to  use  in  other  ratalogues. 


65 


«! 


■i 


OT' 


/tmericap  Steam  Qaa^e  ^o.,  BostOQ. 


AMSLER'8  POLAR   PLANIMETER. 


;: 


r 


FIG.  32. 

There  are  several  other  instruments  which  are  used  as  accessories 
to  the  indicator,  and  whicli  greatly  facilitate  the  using  of  the  instru- 
ment, one  of  which  is  Amsler's  Polar  Planimeter,  as  shown  by  the 
accompanying  cut,  for  measuring  the  area  of  indicator,  diagrams. 
By  using  this  instrument,  the  whole  work  of  measuring  a  diagram 
can  be  done  in  one  minute. 

Engineers  who  have  many  indicator  cards  to  work  up  cannot 
atlbrd  to  be  without  a  planimeter. 


66 


/)m^rka9  Steam  Qau^^  ^o.,  605(09. 


^ 


IHrfrtioHM  for   t'ltlni/  the   tnBtrHiHfHl. 

IVcHi  thr  poitU  y1  sli^litly  into  tlu-  paper,  not  clear  throu);h,  in 
Niich  position  that  the*  tracer  />*  will  follow  the  dvHircd  line  with- 
out hrin^ini;  the  roller  C  against  any  projection.  The  roller  ntUHt 
move  on  a  contiiuionH  flat  Htirface. 

It  iH  also  well  to  tasten  the  dia^^ram  to  a  drawing-hoanl,  or  some 
other  flat  Hurfacc,  hy  means  of  pins  or  sprinf^H,  to  prevent  it  (Vom 
slipping. 

Mark  a  startin^^-point  at  any  point  on  the  outline  of  diagram  J)^ 
set  the  tracer  on  that  point,  and  place  zero  on  the  roller  so  it  exactly 
coincides  with  the  zero  on  vernier  E. 

Now  trace  the  line,  moving  in  the  direction  travelled  by  the 
hands  of  a  watch  ;   stop  at  the  starting-point,  and  take  the  readint^. 

1st.  Find  the  highest  llgure  on  the  roller  that  has  passed  the  zero 
on  the  vernier,  moving  to  the  left,  which  we  will  assume  to  be  4  ; 
now  the  construction  of  the  instrument  is  such  that  each  figure  on 
the  roller  represents  an  equal  number  of  s(|uare  inches. 

2il.  Find  the  number  of  completed  divisions  betwi"'  4  on  the 
roller  and  zero  on  the  vernier,  which  we  will  assume  to  be  5. 

3(1.  Find  the  number  n\'  the  mark  on  the  vernier  which  coincides 
with  some  mark  on  the  roller,  which,  in  this  case,  may  be  6. 

We  now  have  the  exact  reading,  4.56  or  4iVo  '"^bes  area. 

In  measuring  diagrams  of  more  than  10  inches  area,  add  10  to 
the  result. 

To  those  who  are  perfectly  familiar  with  the  instrument,  it  is  not 
necessary  to  place  the  zeros  so  they  coincide;  but  take  the  reading 
as  it  is,  and  subtract  it  from  the  result.  Should  the  second  reading 
be  less  than  the  first,  add  10  to  the  second  reading  before  making 
the  subtraction. 

For  instance,  should  the  first  reading  be  8.42,  and  the  second 
reading  2.68,  add  10  to  the  second  reading,  thus:  2.684-10=12.68 
—  8.42  =  4.26  square  inches. 

If  the  area  to  be  measured  be  very  large,  divide  it  by  lines  into 
areas  of  less  than  20  square  inches,  and  take  separate  measure- 
ments. 

If  the  drawing  be  to  a  scale,  multiply  the  result  by  the  square 
of  the  ratio  number  of  the  scale. 

Should  we  desire  to  find  the  area  of  a  plan  containing  5  square 
inches,  drawn  to  a  scale  of  100  rods  to  the  inch,  we  square  the  ratio 


67 


fim^mai)  Steam  Qau^^  Qo.,  Boetop. 


"^P 


number,  and  multiply  by  5,  thus:  100x100=10,0x50x5  =  50,000 
square  rods. 

In  using  the  planimeter  for  indicator  diagrams,  for  which  it  is 
specially  adapted,  we  find  the  area  of  the  diagram  according  to  the 
foregoing  directions,  which  we  will  assume  to  be  2.48;  we  now 
measure  the  length  of  the  diagram  parallel  with  the  atmospheric 
line,  which  we  will  say  in  this  case  is  4  inches.  Now  divide  the 
area  by  the  length  ;  the  quotient  is  the  mean  or  average  height  of 
the  diagram  in  inches,  which  is  .62  inch.  This  we  multiply  by  the 
scale  of  the  indicator,  which  we  will  assume  to  be  40 ;  the  product 
gives  us  24.8  pounds  mean  pressure  each  square  inch  of  the  piston. 

Expressed  arithmetically,  2. 48-5-4=. 62x40=  24. 8. 

It  can  also  be  used  for  measuring  any  regular  or  irregidar  plot 
or  diagram. 

The  following  is  from  "The  American  Machinist"  of  Dec.  27, 
1879,  by  Chordal :  — 

"The  Polar  Planimetkr.  —  This  little  instrument,  of  which  the  cut  is  about 
three-fourths  size,  is  used  as  the  cut  shows.  The  point  A  is  stationa'-y,  and  the 
tracer  B  is  moved  once  over  the  outline  of  the  diagram.  The  reading  of  the  index 
wheel  Cthen  shows  the  area  of  the  diagram  in  square  inches.  This  reading  divided 
by  the  length  of  the  diagram,  and  multiplied  by  the  scale  of  the  spring,  gives  mean 
pressure  of  the  card.  The  demonstration  of  the  action  of  this  simple  instrument 
would  require  too  much  space,  and  I  will  defer  it.  The  instrument  will  stand  any 
possible  test  for  accuracy,  and  eliminates  all  those  ever-present  chances  for  error 
involved  in  the  human  measurement  of  many  ordinates.  The  time  required  to 
ascertain  the  mean  pressure  of  the  most  ragged  diagram  need  not  exceed,  when  the 
planimeter  is  used,  one  minute.  This  instrument  is  one  of  the  indispensables  to  an 
engineer  having  many  cards  to  work  up,  and  is  a  real  labor-saver.  The  planimeter 
is  the  invention  of  Professor  Anisler,  a  German,  and,  as  made  in  Europe,  was 
intended  for  comprehensive  utility  in  measuring  areas,  and  for  giving  results  in 
sundry  units,  such  as  inches,  feet,  acres,  and  the  long  list  of  foreign  superficial  units. 
This  involved  considerable  complexity  in  the  instrument,  and,  of  course,  a  high  cost. 
F"ew  in  this  country  ever  heard  of  them,  and  but  two  or  three  steam-engineers 
possessed  them.  The  foreign  makers  sent  horrible  translations  of  the  directions 
for  use  with  the  instruments.  Among  other  things,  this  translation  stated,  that, 
'  as  the  principle  of  the  instrument  is  a  secret,  there  is  no  danger  of  others  being 
put  on  the  market.'  This  clause  was  the  cause  of  the  instrument  being  made  in 
this  country.  It  was  a  dare.  Mr.  James  W.  See,  an  engineer  in  Ohio,  took  the 
thing  up,  got  at  the  principle,  redesigned  the  instrument  so  as  to  make  it  specially 
useful  for  such  work  as  indicator  cards,  and  had  quite  a  number  made,  which  he 
sold  and  presented  to  engineers.  They  are  now  made  by  the  American  Steam 
Gauge  Company  of  Hoston,  and,  I  am  informed,  are  sold  with  nearly  all  indicators. 
A  similar  form  of  the  instr.nnent  is  made  by  EUiott  Ikothers,  London;  but  it  lacks 
the  simplicity  of  the  American  one." 


68 


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/tm^rieap  8tean\  (jau^^  (^o.,  Bostoi;. 


^ 


The  planimetcr  is  furnished  in  a  nice  morocco  box,  lined  with 
velvet,  and  can  be  sent  l)y  mail  to  any  place  in  the  United  States  for 
nine  cents. 

The  enormous  sale  we  are  having  of  this  instrument  shows  how 
fully  it  is  appreciafed,  we  being  the  sole  manufacturers  in  the  United 
States. 

Amsler's  Polar  Planimeter  was  awarded  a  silver  medal  and  a 
diploma  at  the  Cincinnati  Industrial  Exposition,  Oct.  8,  1881. 


After  the  second  official  trial  of  tlie  new  U.S.  cruiser  Baltin^ore, 
which  took  place  in  November,  1889,  the  computations  of  these 
diagrams  were  to  be  made  with  the  planimeter  instead  of  by  the  old 
fashioned  methods.  The  diagrams  from  the  second  trial  were  to  be 
computed  first  by  the  U.S.  navy  officers  and  afterwards  by  Mr. 
Thomas  Pray,  Jr.,  of  Boston,  for  the  builders  of  the  ship,  the  Wm. 
Cramp  &  Sons  Ship  and  Engine  Building  Co.  During  the  com- 
putation by  the  navy  officers,  some  questions  arose  which  resulted 
in  their  pronouncing  tiie  planimeter  made  by  this  company  incor- 
rect. We  publish  here,  by  permission  of  Mr.  Pray,  a  copy  (»f  his 
solution  of  the  question  at  that  time ;  also,  his  own  comments  on 
the  subject,  which  were  furnished  by  him,  on  reqiiest. 

"The  decision  with  refertnce  to  the  planimeter  is  only  another  evidence  that 
capable  men  sometim  -s  disagree,  and  that  men  who  mean  to  do  exactly  right  some- 
times make  mistakes.  This  jjow-wow  about  the  i)lanimeter,  as  ap!)lied  to  the 
diagrams  of  the  Haltimore  is  of  a  great  deal  more  importance  than  the  average 
man  supposes. 

"  When  it  is  taken  into  account  that  on  th  •  engines  of  this  ship  one  pound  of 
mean  pressure  on  one  single  engine  is  worth  $;io.ooo,  it  is  evident  that  correct  com- 
putation of  the  cards  ceases  to  be  an  amusement  and  becomes  a  veritable  fact. 

"  I  have,  therefore,  taken  a  personal  int»'resf  of  no  small  amount  in  demonstrat- 
ing to  my  own  satisfaction  that  your  jjlanimeter  was  cither  right  (  r  wrong,  without 
any  ifs,  buts  or  ands.  Here  is  a  little  solution  that  I  give  you  my  permission  to 
print,  only  stipulating  that  you  shall  C've  me  credit  for  it.  It  is  this  :  if  the  plan- 
imeter is  not  correctly  used  it  is  incorrect  in  its  rt.  ults  to  a  very  small  extent.  If 
correctly  used,  I  have  found,  in  the  work  with  reference  to  the  U.S.  cruiser  Haiti- 
more,  which  I  am  now  doing  in  Philadelphia  for  the  W  m.  Cramp  &  Sons  S.  and 
E.  B.  Co.,  that  these  errors  are  larger  in  the  person  th-^i  in  the  inttiumcnt;  that 
the  instrument  is  cnp.  iWe  of  measuring  an  indieator  diagra.n  nearer  correct  than 
the  person  's  of  traversi.ig^the  same  line  the  second  or  third  or  any  other  number 
of  times,  and  coverin;^;  absolutelj  the  same  area. 


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P{t\er\Qat)  Stea/n  (jau^e  ^o.,  Bostop. 


^^ 


"This  makes  the  actual  error  of  the  inatrunicnt,  by  careful  running,  less  than 
I  in  17CX).     Here  is  the  way  to  get  correct  results  :  — 


J 


1 


"Take  any  piece  of  cardboard,  Bristol  board  or  strong  paper,  draw  on  it  the  line 
as  in  the  figure  A,  any  length  you  please,  preferably  about  8  inches  long,  at  right 
angles  to  the  line  A,  draw  the  line  H,  which  may  be  any  length  you  please,  wider 
thiin  the  total  width  of  the  paper  on  which  an  indicator  diagram  is  taken,  but  the 
line  H  must  be  drawn  at  exactly  4.34  inches  from  the  point  on  line  A  where  the 
other  line  intersects  the  long  one,  or,  in  other  words,  the  distance  between  A  and  H 
must  be  as  nearly  4  5-16  inches  as  can  be  laid  down  by  an  ordinary  rule.  Then  put 
the  point  of  liie  planimeter  at  A  and  put  the  card  to  be  computed  so  that  half  the 
height  shall  be  above  and  half  below  the  line  A,  and  half  the  length  to  the  right 
and  half  to  the  left  of  the  line  li.  Then  if  the  reading  pointer  of  the  planimeter 
is  correctly  manipulated,  the  exact  area  of  the  figure  will,  in  every  case,  be  ob- 
tained, so  long  as  proper  care  is  exercised  in  reading. 

"  This  will  allow  the  use  of  high  pressure,  condensing,  compound,  locomotive,  air 
pumj)  or  any  other  kind  of  card  to  be  ctnnputed ;  and  if  the  lines  are  drawn  in  ink 
and  the  distance  is  carefully  measured  and  the  planimeter  properly  managed,  they 
will  be  found  far  nearer  correct  than  the  power  of  the  person  using  them  to  repeat 
his  own  measurements  absolutely.  This  was  the  result  among  the  naval  engineers, 
after  the  use  of  a  large  Amsler's  planimeter,  obtained  from  the  navy  department, 
and  the  actual  difference  in  measurement  of  the  same  diagram  between  their  and 
my  own  large  Amsler  was  i  in  2400,  and  the  difference  between  my  own  large 
Amsler  and  my  American  Steam  Gauge  Amsler,  No.  231,  which  I  have  used  for 
several  years,  and  three  other  American  Steam  (lauge  Amslers,  loaned  for  the  pur- 
pose, was  a  little  less  than  i  in  1800  for  the  whole  four;  but  by  distorting  the  posi- 
tion of  the  instrument  with  reference  to  the  figure,  without  the  use  of  the  simple 
diagram  enclosed  herewith,  the  errors  of  the  little  Amslers  were  as  high  as  i  in  560, 
and  this  error  immediately  vanished  w'len  the  position  of  the  same  instrument 
was  corrected  by  the  two  black  lines  drawn  on  a  piece  of  drawing  paper,  the  same 
as  is  referred  to  in  the  figure  above. 

"  It  is  not  necessary  that  the  diagram  should  be  placed  perfectly  parallel  with  the 
line  A,  but  it  may  be  placed  at  any  angle  to  either  line,  so  long  as  the  centre  of  the 
area  to  be  measured  is  kept  over  the  intersection  of  the  lines  A  and  B.  This  is 
particularly  the  case  whenever  the  diagrams  are  taken  4  3-4  or  5  inches  long:  or  the 
tliagram  may  be  inverted  and  the  vacuum  line  or  the  atmospheric  line  be  nearest 
tile  instrument,  or  above  the  line  A  instead  of  below  it. 

"  You  have  my  permission  to  make  use  of  this,  by  credit,  in  any  way  you  see  fit 
which  is  for  your  advantage  and  for  the  beivefit  of  the  thousands  of  men  who  are 
using  your  instruments." 


70 


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I  m 


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pmeriQap  St^am  (^au^e  Qo.,  Bostoi^. 


^ 


TESTIMONIALS. 

[copy.] 

Navy  Dkpartment,  Hureai'  ok  Stkam-Kncjinkkrinc;, 
Washincton,  April  7,  1879. 

Sir, —  In  obedience  to  your  order  of  the  5th  inst.,  we  have  carefully  examined 
the  Polar  Planimeter,  submitted  by  H.  K.  Moore,  and  find  it  to  be  identical  in  design 
with  Amsler's  improvement  on  the  original  instrument  of  Appenkofer,  but  unpro 
vided  with  attachments  for  changing  the  scale,  or  for  recording  the  revolutions  of 
the  index  roller. 

The  instrument  submitted  is  light,  neatly  and  well  made,  and  all  its  working 
parts  accurately  fitted,  and  capable  of  delicate  adjustment. 

It  can  be  readiiy  manipulated  by  any  person  of  ordinary  intelligence ;  and,  in  our 
opinion,  its  use  will  greatly  facilitate  the  work  of  measuring  the  areas  of  irregular 
figures,  and  will  be  particularly  valuable  to  the  Hureau  for  determining  the  mean 
pressure  of  indicator  diagrams. 

Very  respectfully  your  obedient  servants, 

H.  W.  FITCH,  Chief  Enghuer,  U.S.N. 
DAVID  SMITH,  Chief  Kngincn;   (\S.N. 
H.  WEKSTER,  P.A.  Engineer,  U.S.N. 

To  Engineerin-Chief  Wm.  H.  Smock,  US.N., 

Chief  of  Bureau  Steam-Engineering,   Washington,  D.  C. 

Icopy.l 

Office  ok  John  W.  Hill,  Mechanical  Enoineer, 
CiKciNNATi,  O.,  Dec.  29,  1879. 
H.   K.   Mooee,  Esq.,  Boston,  Mass. 

Dear  Sir,  —  Upon  my  return  frr-m  St.  Louis,  last  week,  I  found  your  kind 
remembrance  of  the  writer  in  the  shape  of  a  new  planimeler,  for  which  you  have 
my  sincere  thanks. 

I  have  carefully  tested  the  instrument,  and  it  varies  but-j^Voinr '"  the  circuit. 

Very  sincerely  yours, 

JOHN  VV.    HILL. 

...  By  its  use,  diagrams  may  be  carefully  and  correctly  measured  in  one  minute, 
everything  l)eing  taken  into  account,  and  the  actual  area  found. 

THOMAS  PRAY,  Jr. 

PKJC'JS  or  THK  PLAJflMKTEH,  ALL   S H.KKL-Pl.Al^.i,,   Afilt 

IS  A    VEhVET'LINlCIt  BOX .        .   $lff,or 


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/tfn^rieaQ  3^®^^  (jau^^  ^o.,  BostOQ. 


RICHARDS    PARALLEL-MOTION 
INDICATOR. 


FIG.  33. 

This  indicator  has  been  long  and  well  known  with  the  engineer- 
ing public.  It  is  not  adapted  for  high-speed  engines,  but  is  per- 
fectly reliable  and  accurate  for  engines  making  less  than  eighty 
revolutions  per  minute. 

PRICE ,        .       .        $85.09 

Extra  springs,  scales,  cocks,  elbows,  etc.,  same  price  as  those 
u<ed  with  the  Thompson  Indicator. 


73 


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THOMPSON  IMPROVED  INDICATOR. 


v/         ez-K-- 


